Search Results for: Blackface%20Vibroverb


Fender Amplifiers

Founded in the mid-1940s in Fullerton, California by Leo Fender, the legendary amps produced by this company have been heard on countless recordings and are influential on countless other amp makers. In the beginning Fender paired small combo amps with lap steels and electric guitars aimed at student players, but word of the superior tone and build quality quickly spread among professional musicians. In over seventy years of existence, Fender has consistently evolved and innovated its sound from the Tweed era through the Brown and Blackface eras and beyond.

Mercury Magnetics has built a massive collection of ToneClone® Transformers and Chokes for Fender Amps available from all eras of production. Answering the needs of players and amp-builders alike, our extensive catalog of audio transformers is the ultimate resource whether you’re looking to replace a worn-out transformer in a vintage Fender amp or looking to nail a vintage tone in a new amp or amp build. The engineers at Mercury have painstakingly documented every detail and nuance of the best-of-breed vintage transformers and can faithfully produce perfect clones using the same materials and methods used on the originals.

The ToneClone+ Series from Mercury Magnetics adds more utility and options without altering the original tone. Love your amp but want to change your speaker configuration? Mercury’s ToneClone+ Output Transformers give players more impedance options like alternate and multi-tapped secondaries. Power Transformers can benefit from the “Plus” treatment as well with alternate primary voltage, Higher or Lower B+ Voltages, added current capability, and more.

Fender Woodie Amp Transformers: The earliest production amps to come out of Fullerton, Fender ‘Woodie’ amps can be identified by their hardwood cabinets and fixed handles. We are proud to offer ToneClone® transformers from this short-lived and rare Woodie era including the Woodie Deluxe (aka Model 26) and Woodie Pro.

Fender Tweed Amp Transformers: The Fender Tweed era lasted from the late forties to early sixties and a vast amount of artists from all generations have crafted their distinct tone using these amps through all genres. Notable artists include: Scotty Moore (Elvis Presley), Neil Young, Larry Carlton, Eric Clapton and Keith Richards. Mercury Magnetics has the largest catalog of vintage-correct Fender ToneClone® replacements transformers for the following models: Tweed Bandmaster, Tweed Bassman, Tweed Champ, Tweed Harvard, Tweed Princeton, Tweed Pro/Dual Professional, Tweed Super, Tweed Tremolux, Tweed Deluxe, Tweed Twin, and Tweed Vibrolux.

Fender Blonde and Brown (Brownface) Amp Transformers: Sitting on the timeline between the Tweed and Blackface Fender amps, the Blonde/Brown amps of the early sixties were most noticeably embraced by surf groups like the Beach Boys and Dick Dale. Our catalog of ToneClone® amp transformers for this era includes Brown/Blonde Bandmaster, Blonde Bassman, Blonde Showman, Blonde Tremolux, Blonde Twin, Brown Concert, Brown Deluxe, Brown Princeton, Brown Pro, Brown Super, Brown Vibrasonic, Brown Vibrolux, and Brown Vibroverb. Also see our transformers and choke for the 6G15 Reverb Unit.

Fender Blackface Amp Transformers: Easily distinguishable by their black control plates and white lettering, Fender Blackface amps began showing up on stages and recordings in the early-mid 1960s. Extremely popular among musicians then, the impressive build quality and versatile tones have kept these classic amps popular even 50 years later. Mercury Magnetics has hundreds of ToneClone® and ToneClone+ transformers and chokes for Fender Blackface Amps including: Blackface Bandmaster/Bandmaster Reverb, Blackface Bassman, Blackface Champ, Blackface Concert, Blackface Deluxe/Deluxe Reverb, Blackface Princeton/Princeton Reverb, Blackface Pro/Pro Reverb, Blackface Showman, Blackface Tremolux, Blackface Twin Reverb, Blackface Vibrochamp, Blackface Vibrolux, and Blackface Vibroverb. Also see our transformers and choke for the 6G15 Reverb Unit.

 

Ordered a Black-face Pro Tone Clone Guitar Amp Transformer

Fender designed and built more than one transitional, non reverb blackface combo amp that would soon acquire reverb and a new name, including relatively small numbers of blackface Princetons, 4×10 Concerts, 1×12 Vibrolux and 1×15 Pros. We acquired a 1×15 blackface Pro, and while it ultimately proved to be an extraordinary exceptional amp, we were also reminded of the potential pitfalls that exist when buying old amps sight-unseen, as well as the potential rewards.

We found the ’64 Pro listed on eBay and bout it from a dealer after requesting a detailed photo of the chassis and circuit. Proudly described as “the best amp in the store, “the rare ’64 blackface Pro is essentially a blackface Vibroverb without the “verb.” Do we have your attention yet? Three caps had been replaced, the original baffleboard had been professionally converted to plywood with the original grill cloth remaining intact, and an on/off pot had been installed for the tremolo intensity control that bypassed the tremolo circuit when rolled to “1” with a click, adding gain that would otherwise be missing in the Vibrato channel. We pulled the JJ power tubes and assorted Russian pre-amp tubes and replaced them with lightly used,“test new” RCAs from our stash, rebiased the amp and fired up the Pro….

Sounded like shit. We had been here before with a dead-mint ’64 Vibroverb bought years ago that had passed through a certain amp guru’s hands in Pflugerville, Texas.How could a vintage Fender sound so bad we wondered? Turned out that the value of the bright cap on the Vibrato channel had been changed on the Vibroverb, rendering a thin, scalding tone that would have given Ed Jahns fits, as it did us. Changing the bright cap back to spec immediately restored the Vibroverb to its rightful pace in history, but the Pro had other problems….

The baffleboard swap and added switch on the tremolo intensity control were clues that someone had also spent time troubleshooting the amp, probably trying to detect the cause of the Pro’s weak output, thin tone and curiously harsh edgy distortion. The amp just didn’t sound right. We pulled the original, reconed Jensen C15N dating to 1964 and subbed in an Eminence Legend, but the Pro still sounded choked-off, linear and wrong, so it was off to Jeff at Bakos Amp works on the Friday afternoon before Memorial Day weekend in a frog-chokin’ Georgia thunderstorm. When the going gets weird, the weird turn pro…..Now, this is the difference between someone who really knows his craft and a hack….Jeff plugged his bench guitar into the Pro, hit a couple of chords, issued a single grunt of displeasure and caustically observed, “Something is definitely fucked up.” With the chassis on the bench, Jeff scowled at the choppy sine wave the amp produced on his scope as he checked voltages with his multimeter. “I think the output transformer is going down slow—it measures 11 volts and it should be reading 16….” He clipped in a substitute OT from a stout old Fisher hi-fi, plugged in and hit a chord… “That’s closer to what it’s supposed to sound lie….” And sure enough, the missing lows and mids were present, the raspy treble tones were subdued, and for the moment, the Pro showed promise. We called Paul at Mercury Magnetics and ordered a black-face Pro Tone Clone replacement trans-former, shut it down and wished each other a good holiday. A week later the Mercury Magnetics replacement output transformer had arrived. Jeff wired it up, and then turned his attention o three silver mica caps that had replaced the original ceramic caps in the phase inverter and tone circuits. Jeff: “Somebody probably read an article about how these would bring the high end up, but I prefer the ceramics—always have. Besides the effect of the voltage from the old output transformer being low, these silver mica caps were contributing to that brittle tone we were hearing. They are the wrong value, and they changed the entire sound of the amp.” Jeff pulled all three silver mica caps and replaced them with the correct ceramic disc caps, and since an on/off switch had already been installed for the tremolo, we mounted the 25K mid range pot in the back panel hole for the extension speaker jack. With the Pro now thoroughly put right and the midrange pot added, Jeff hit a few chords, moved the EQ and volume settings around a bit in both channels, smiled and said, “That sounds really good. Yeah, that’s it.”

Back in our music room, the final step was to re-bias the Proat 34mA with an AmperexGZ34 rectifier and our last pair of vintage RCA black plate 6L6s, which in unused, new old stock condition have soared to $400/pair. The re-labeled Tube NOS Phillips JAN 6L6 WGBs we had tried sounded good—but the smooth warmth, exceptional musicality and deep harmonic content of the RCAs just can’t be beat, and it is a difference you can definitely hear. Smoke ’em if you got ’em….

We lit up the Pro with the ’63Fender Reverb unit and reverently smiled at the jaw-dropping tones pouring from the big Eminence Legend 15. Imagine the sound of a slightly kinder, warmer sounding 40 watt Super Reverb void of the sharp, penetrating treble presence that has sooften left our ears ringing for hours after a tumble with a blackface Super. The sound of the ’64 Pro is all Fender, with solid bass that doesn’t fall apart at high volume as the smaller blackface combos can,sweet, singing treble tones, and now… a mid range control that can gradually push the amp beyond its original, clear and liquid “scooped” mid range voice to an exceptionally thick, “mid-Atlantic” roar that unleashes heavy sustain and rich, musical distortion as only a Fender can. The Pro brilliantly complements every guitar we own, producing the essence of classic Stratocaster, Tele, P90 and humbucker tones with clarity, depth and lush fidelity that literally fills the room. Yes, there are different and equally worthy tones to be had from the British classics,but we have never heard a more beautiful sounding or versatile Fender amp—one that can range from crystalline, blackface clarity to the full burn of an early blonde Fender Bassman at much friendlier volume levels. The Pro can get plenty loud, but it’s a loud that doesn’t kill you in the style of a Showman, Twin or a Super Reverb.

The irony in this unexpected discovery has not escaped us,and perhaps the weight of it is now becoming clear to you, too. This project did not begin well, and we confess to experiencing some remorse when the Pro arrived with a few bad mods, weak and thin from the original output transformer going down, and generally just sounding very wrong. Our dismay was soon displaced by genuine enthusiasm; however, as we were reminded that this is indeed what the quest for tone is all about it. We’ve acquired absolutely bone stock amps in perfect working condition that just couldn’t tote the note, so why should we expect to buy a 44 year old amp that’s been played without it needing a little repair and restoration work? The end entirely justifies the means.

Having finally experienced the Pro’s singular, exceptional sound, we wondered what had caused it to be relegated to such obscurity among all the Fender black face amps. Like the Vibrasonic and Vibroverb, perhaps it was doomed by the presence of the single 15” speaker. Like the Pro, the blackface Vibroverb 1×15 was produced for less than a year, and with the introduction of the 2x12Pro Reverb in 1965, Fender would no longer produce a 1×15 combo until the introduction of the silver face Vibrosonic in 1972. Yet, the earlier 1×16 Pros had been Fender’s flagship amps during much of the tweed era, and in 1960 the 1×15 brown Pro ranked second only to the1x16 Vibrasonic in the Fender catalog. Somewhere along the way, the 1×15 combo had clearly fallen out of favor with Fender, guitarists, or both, and given the short life span of the Vibroverb, even the addition of reverb couldn’t save it.

Twenty years later, Stevie Ray Vaughan elevated the Vibroverb to hall of fame status, otherwise, the 1×15 com-bos seem to have been perceived as “uncool” for anything bug jazz and blues, as if wearing a jacket and tie were required to play them. The Pro is a great blues amp, but it’s also a great rocker, and equally well-suited for jazz, pop and country. With far more clean head room and power than any tweed Pro and much stronger distortion, sustain and dynamic character than a brown Pro, the blackface Pro reflects Fender’s ongoing pursuit of more powerful, cleaner sounding amps, but unlike the black face Bandmaster, Tremolux and Showman, and Pro can really rock the house cranked. We suspect it’s a single 15 and missing ’verb that throws people off today, yet in’64 Pro shares its DNA with the ’64 Bassman and all the highly prized blackface combo amps, including the Deluxe Reverb, Vibrolux Reverb, Super Reverb and the heavily prized and hyped Vibroverb.

The contrast between the Vibroverb’s Holy Grail status versus the lowly blackface Pro simply underscores how easily we can be blown off course by what isn’t hyped on the Internet or in print, and by the powerful logic that suggests if anything 44 years old is truly noteworthy, “we” would already know about it. Well, apparently “they” don’t. But you do. Blackface Pros can be found for $1 500–$2,000,with originality and overall condition driving prices accordingly. Like the Deluxe, we wouldn’t buy one that has had all the blue molded capacitors or Allen-Bradley resistors replaced, but the transformers available today from Mercury will sound every bit as good or better than the originals, and as we have said so many times in the past,the Eminence Legend 15 is spectacular. Add some good,current production or NOS tubes and you will have been delivered to a place well beyond the common man’s limp and shriveled imagination. Now Quest forth….

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Feature Rich Guitar Amplifiers Review

We told this was coming.. Tes, when readers ask us to review something, we do our best to respond, and thanks to RedPlate founder Henry Heistand, we received two RedPlates for review. We’ll start this episode by telling  you that Henry Heistand appears to be a very clever fellow who is not working in the shadows of that past, which is to say that he builds feature-rich amplifiers that in no way pretend to be vintage knock-offs. Play a RedPlate and you’re firmly treading in the present, rather than mining tone out of a dusty box built by a dead man (or woman—sorry Lily). And that’s fine. There is certainly ample space in these pages for the living, and RedPlates are in fact very lively tools indeed. We asked Henry to give us a glimpse into his background and motivation, and our reviews of the TweedyVerb and BlackVerb follow….

TQR: How and when did you initially become involved in electronics and amplification?

HH: Starting around age 12 playing to the radio and jamming with friends, my first build attempt was a speaker cabinet made out of ½ plywood and covered with yellow carpeting. It had a leopard (spotted) grill cloth and contained 6 speakers recycled from various old TVs and stereos. My first real amp repair was replacing a screen resistor in a Fender Bassman in 1970. I went to college for a year and then played guitar full time until 1979 when I attended electronics school (they still taught tubes). To pay for school I got a part time job at a church organ repair shop that had a “combo” repair department and still played in club bands on weekends. Attending electronics school in the morning and repairing gear in the afternoons was a great way to instantly translate the classroom to the real world. Compared to the tube TVs and tube broadcast transmitters, the tube musical amplifiers were relatively simple. Besides Fender and Marshall, tube amps by Sunn, Ampeg, Gibson, West, Park, Hiwatt, Sound City and all the Supro/Kalamazoo/Dan Electro stuff. If I only had a nickel for every good tube I tossed in the trash back then. Many of those same companies had solid-state amps too along with companies like Acoustic, Kustom, Peavey, Randall, Lab, SG and Roland. It seems like the ’70s was the golden era of guitar amp designers. Although most tube amps have a similar topology, the differences between brands in those days ranged from truly innovative to laughable. On a few occasions when a solid-state repair would come in that was totally fubar, one of the church organ repair guys would show me how to design a new circuit right over the top of the problem area, teaching me the value of having a few simple circuit designs at the ready for emergencies. In late ’82 I got a career job in the computer field, and by ’86 purchased the part of the church organ repair shop that repaired the “combo” gear. The new company was named Music Mechanix and kept the warranty contracts with all the majors for amps, keyboards and P.A.s.

TQR: As you became more familiar with various amp designs of the past, what were your favorites and why?

HH: Thinking back to the tonal memories accumulated during those years spent repairing amps, the most musical of all of them were probably the early ’60s Fender tube amps. In addition to repairs, Music Mechanix did all the popular mods of the day (anyone remember the original Train Wreck Mod pages for Fenders?), many times we would redo almost everything inside but keeping the exterior unchanged. Most of my playing back then was strictly radio cover songs so the quest was always to find the one amp that could imitate everything. Music Mechanix was continuing the warranty station status from the previous owner (established in the ’50s) so every original manufacturer’s amplifier schematic ever released was available as a reference source, residing in 16 large file cabinets. On the side, I kept a little notebook of circuits and mods of interest to use as building blocks.

TQR: Can you describe the lasting impressions created by your study of the experiences with classic amps that have most affected your own design philosophy and preferences?

HH: As a service to friends and regular customers Music Mechanix would take a classic amp (at the time it was easy to get something like a used Bassman for $100) and do Frankenstein amps that were Fender this, Marshall that, with a sprinkling of Vox and Ampeg thrown in depending on the customer’s needs. On the weekends I was doing gigs using a pair of modified Ampeg VT-40s in stereo until somehow I ended up with a Mesa Boogie S.O.B. that had a really innovative phase inverter section controlled by a “LIMIT” knob. A bizarre variation of a PI section’s constant current source, the circuit was not in the RCA manual or on any other schematic. It sparked something in me and from hen on I started doing creative amp mods that were not copies of things I had seen on schematics.

TQR: When did you first begin to sketch out the concept for RedPlate amps, and what did you want to accomplish that would be unique and different?

HH: I had always been fascinated with “sleeper” amps that looked small but sounded big. After selling the repair business I used my free time to do a lot of experimentation on point-to-point builds in a Fender Camp sized chassis, eventually working out how to do a 7 tube, large transformer build in a Champ chassis without noise or oscillation. My favorite guitar tones were the recorded sounds of the Mesa Boogie/Dumble ODS type amps (even before I even knew what a Dumble amp was). A clean singing tone with a hint of character that sustains and blooms is my idea of the ultimate tone and the design goal of all the RedPlate models.

TQR: Can you briefly describe the unique features and differences among the current line of RedPlate models?

HH: RedPlate probably has too many models because we treat the sections as modular building blocks. We start with one of the 3 chassis sizes:

CH1. 15” width with four 9 pin sockets and two 8 pin sockets, transformers up to the 50 watt size.

CH2: 17” width with six 9 pin sockets and two 8 pin sockets, transformers up to 80 watt size.

CH3: 19” width with five 9 pin sockets and four 8 pin sockets, transformers up to 160 watts

Then we use different combinations of the building blocks with the only limitation being the number of controls (physical knob space) and the number of tube sockets available. Building blocks currently in use:

BB1. PREAMP1—Tweed—A single tone knob preamp (Tweed style).

BB2. PREAMP2—Blackface—A Treble, Middle, Bass Preamp (Blackface style).

BB3. DRIVE1—A three knob overdrive section (Gain, Drive, and Level).

BB4. DRIVE2—A six knob overdrive section (Gain, Drive, Level, Treble, Middle and Bass).

BB5. REVERB—A single knob tube reverb with medium decay tank.

BB6. EFFECTS LOOP—A fully buffered serial loop, return level is the master volume.

BB7. PHASE INVERTER—Standard Long Tail pair, very similar to the early ’60s designs.

BB8. POWER AMP #1—40 watts cathode bias (6L6GC).

BB9. POWER AMP #2—50 watts fixed bias/40 watts cathode bias (6V6GC)

BB10. POWER AMP #3—80 watts fixed bias (KT-88).

BB11. POWER AMP #4—45 watts fixed bias/18 watts cathode bias (6V6GTA)

BB12. POWER AMP #5—100 watts fixed/50 watts fixed (6L6GC).

TQR: Both of our review amps are loaded with Warehouse speakers from Kentucky, which we have reviewed before. How extensive are your evaluations of various speakers when creating a new model? Does the same process apply with transformers, tubes or other components?

HH: The current lineup is using WGS Retro 30, WGS British Lead 80 and Eminence Swamp Thang speakers in the combo amps. The decision to use these was based on side-by-side comparisons with other brands (an ongoing process).

Tube selection is mostly based on reliability (as long as the tone is still there). The current production amps use Svetlana 6L6GC, SovTek 12AX7LP (PI tube), and Electro Harmonix 6V6GTA and 12AX7s (preamp).

Selecting individual signal path components is more difficult because side-by-side comparisons can be misleading (no 2 amps are exactly alike). The signal path in current production amps use PS series Orange Drop capacitors and carbon film resistors based on low noise and musical warmth in the tone. RedPlate Amps has a good relationship with Mercury Magnetics and I like to use their transformers in most models.

TQR: How does the half power switch function in your amps, as well as the “mode” control and various voicing controls?

HH: Depending on the output section, 3 methods are used:

1. 6L6GC 100 watt/50 watt—The switch lifts two of the four tubes by 10K so they are effectively out of the circuit yet the impedance selection is still valid.

2. 6V6GTA 45 watt/18 watt—Full power runs two of the tube in cathode bias and two in fixed bias, the switch lifts the fixed bias tubes by 10K to effectively remove them without changing the output impedance.

3. 17 Watt (Hi/Lower)—This switch just lowers the voltage to the phase inverter tube so the amp breaks up sooner. There are two different styles of mode switches. On the Tweed style preamps the 6 position mode regressively reduces midrange and preamp output to imitate a Blackface style amp. On the Blackface style preamp the 6 position mode switch progressively fattens the midrange to imitate a Tweed style amp. Most of the models also include a Humbucking/single coil switch to set the amount of bass gain in the input stage.

TQR: How much individual customization or voicing do you offer for specific models when working with an artist?

HH: Unlimited customization is available, although most of the professionals that use RedPlate Amps are content playing standard models.

TQR: We noticed that you include the owner’s name on the back panel, correct? A nice touch…

HH: Yeah, the front and rear panels are done in-house, we could even put pictures of your dog on there.

TQR: What do you want to accomplish in the future? New models?

HH: “Amps that sing” being every guitar player! Going forward, curiosity and customer feedback will continue to drive the evolution of current designs and the development of new designs. For example, there will be a “shredder” amp in the near future (The ShredPlate) and possibly a bass amp. As RedPlate continues to gain name recognition with the music industry, models like the BlackVerb, MagicDust and TweedyVerb will hopefully be taken for granted as standard amplifier types.

The front and rear panels on the BlackVerb reveal an impressive array of controls, push/pull-knobs and switched pots. In fact, the printed operation guide includes a signal path diagram on the front page with a welcoming invitation to skip an in-depth review of the manual and just set all the knobs at 12 noon and play, which we did, consulting the manual as needed as we spent more time with the amp. So, is the BlackVerb too complicated for you “plug & play” guys? Not really, but the control panel is best reviewed in sections. You’re essentially working with a clean preamp circuit and a Drive section that includes Gain, Drive and Level controls for variable levels of distortion overdriven tones, but there are still many more additional tweakable features lurking within…

The first control adjacent to the single front input jack is the miniature Bright switch toggle with the center position OFF, Down producing the sound of “new strings” (an accurate description we might add), and Up rendering a brighter tone that will be familiar to those of you with a Fender Blackface amp with bright switch. We usually use the bright switch to put a little extra shimmer and spank on humbucking pickups, or neck pickups on single coils.

The Volume control includes a pull switch to engage a midrange boost that increases upper mids. The Middle control does what you’d expect, with a pull switch for a “Deep” setting that scoops mids and boosts bass frequencies—an excellent change-up for clean tones. The Bass control handles low end quite well, and it can be clicked OFF to be removed from the tone stack. Try that with a neck pickup and it produces the odd and very different EQ found in some old Valco and Gibson amps.

The Mod Selector is a 6-position rotary EQ switch that gradually produces a fatter, thicker tone as you rotate left to right from the “Funk” setting, to “Normal” and “Fat” (tweed). All this pulling and turning may sound complicated, but you’ll have it thoroughly digested in 5 minutes, and most importantly, these extra EQ controls expand the tonal capabilities of the BlackVerb in a clever and creative way that really is worth using and exploring. We have bitched about such bells and whistles on other amps having limited value, but no such questionable affectations plague the BlackVerb. Like we said, Henry is a clever fellow. On the Drive section…

This is where you mine and manage overdriven tones and distortion. The Gain control can be bypassed by clicking fully left, otherwise, you’re setting the amount of signal being sent to the first gain stage, which produces variable levels of smooth growl and grunt. The Drive control further ramps up distortion through two gain stages, and a pull switch on the knob serves as an afterburner for maximum burn and rip. At this point you will be channeling Metallica at full husky, so hide the dog. The Level control sets the output volume for this section, resulting in a progressively bigger, thicker, bolder voice. Of course, the big selling point for the BlackVerb is how all of your clean, moderately busted up and filthy dirty tones can be deftly tweaked and the volume managed with the Volume and Master volume controls. At the full power setting, you really can get this thing to sound like a 100 watt high gain amp on “7” at low decibel levels suitable for home recording and friendlier sound pressure levels.

The reverb control is what it is, and you can turn it off fully left and it’s out of the circuit. The Presence control is described as using “global negative feedback to remove low frequencies which frees up bandwidth for more midrange and highs,” and it can also be turned off when rotated fully left. Frankly, the appeal of this control escaped us, but we can imagine how it might be useful in a live situation where you may want to avoid too much low end muddying up the mix with bass and drums. The Master volume works very well without producing the dreaded master volume/low volume faux zizzz when you’re trying to light a fire at low volume levels.

One of our favorite features is the 50 watt/40 watt switch on the back panel that changes the boas from fixed to cathode for a completely different feel. With the 40 watt cathode biased setting you can also change the 6L6 output tubes to 6V6s, transforming the BlackVerb into an 18 watt cathode biased flame thrower, or bypassing the Gain section for a more tweedy character and voice. The Hi/Lo power switch changes the voltage on the input stage and the threshold for clean headroom.

The back panel Smooth switch is just that, adding slight compression in the clean preamp, and the Humbucker/Single Coil setting sets the amount of bass gain in the input stage, relieving you of perhaps resetting EQ when switching from single coils to humbuckers.

Additional utilitarian features on the back panel include a handy bias adjustment and test point, speaker impedance selector, main and extension speaker jacks, FX send and return, and footswitch jack. The footswitch gives you the capability to get in and out of the Tweed, Drive and Boost circuits. Tweed boosts upper mids while lifting the midrange control on the front panel for maximum push in the frequencies where the guitar really lies on stage. Drive engages the Drive feature, bypassing it when off at the footswitch. Boost makes everything sound bigger with a partial tone stack lift.

And now for the bottom line…. It seems to us that the intention of the BlackVerb is to be as tonefully versatile as a 1×12 combo amp can possibly be whether you are playing small clubs, bigger rooms or wide open outdoor stages. You could play nothing but smooth, clean jazz through this amp without ever venturing into the gain stages and be perfectly happy. Or you could do nothing but feast off the considerable gain and distortion lurking in the heart of the BlackVerb and be equally happy. Most gigging musicians want to range between such extremes living somewhere in the middle, and you can do that, too. Like most feature-rich amplifiers, you’ll find certain favorite settings that will be revisited with specific guitars, and after a few days you’ll have no trouble quickly accessing those settings, although the control panel is a bit difficult to read until you no longer need to read it at all.

The standard Warehouse Retro 30 speaker is a brighter version of the Veteran 30 we have favorably reviewed in the past. Given the considerable range of overdrive and distortion available in the BlackVerb, the Retro 30’s clear, articulate character and exceptional capacity to handle low frequencies makes it an excellent choice for this amplifier. Even at extreme gain and drive settings, the BlackVerb produces a rich and musical burn that does not mask or obscure essential overtones and harmonics. The clean tones are equally strong, powerful and clear, and the amp will nimbly spill into overdrive played clean at higher volume levels that can be managed with the volume on the guitar. The BlackVerb impressed with its ability to embody many different styles of amplifiers in one compact box, limited only by your capacity for experimentation and your imagination. Imagine that.

We were particularly anxious to experience the TweedyVerb because it seems to fit the power and volume requirements of so many players today, and it is a very straightforward and versatile 1×12 combo that is a breeze to hump to the next gig. Got your attention there, did we? We finally figured out why vintage blackface Pro Reverb amps have remained relatively underpriced… just pick one up.

The TweedyVerb is a cathode biased dual 6L6 amp with reverb, loaded with an 80 watt Warehouse British Lead 12” speaker. You won’t find a bad tone in this amp, and the controls are very intuitive, delivering outstanding “blackface,” “brown” and “tweed” tones via a 6-position Mode switch. The Bright switch is identical to the BlackVerb (you’ll love the “new strings” setting), with a single Volume control, simple Gain control, and a Tone control that can be clicked off fully left to bypass the tone stack for a very heavy and thick does of overdriven tones with excellent dynamic feel and touch sensitivity. The spring reverb is good—delivered form an original new old stock Accutronics pan made by Cary, IL, and the Presence control is identical to the BlackVerb, using global negative feedback to remove low frequencies and emphasize mids and highs. It also seems to decrease volume and gain, best used in our opinion for clean tones.

The 40 watt/17 watt switch on the back panel changes the voltage on the phase inverter. We preferred the sound and girth of the 40 watt setting, which still allows plenty of room for managing volume and variable distortion with the Gain and Volume controls, but the 17 watt setting is fine, too for close quarters. 6V6 power tubes can also be used at this setting without re-biasing for lower power output and volume. A footswitch is included to access both the fat Tweed setting on the Mode switch on the fly, and the Boost function, which acts as a tone stack bypass. Despite its compact size and relatively light weight, the TweedyVerb is a big-sounding amp that produces outstanding clean tones at usable stage volume, yet it can also be gradually pushed into the familiar sound of a Deluxe Reverb on “6” or even a vintage Marshall head at higher volume and gain settings. It’s a right fair chameleon, this one.

The Warehouse 80 watt British Lead 12 gracefully handles the power output of the TweedyVerb with excellent clarity, sold bass, vivid mids and a sweet and chimey top end. Like the BlackVerb, the TweedyVerb offers the sound and feel of several distinctively different amps in one box via the Mode switch, and we liked them all, from the rough and tumble Tweed, the slightly less raucous, smooth upper mid voice of the Brow, and the more scooped, open and airy Black settings. Both RedPlate models reviewed here clearly share the same DNA, which is to say that they possess a remarkably rich and music character, whether you choose to stroke big clean tones through them or dial up a tone that would make Billy Gibbons proud. Douse that light, and Quest forth….

 

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Replacement Transformer

New Amps on the Block: The Sound of History and Innovation

Byers Amplifiers is a new company with the unique outlook and values of its founder. Trevor Byers worked at the Fender Custom Shop and has seen it all, from carefully reproducing old vintage gear to building new guitars to exacting specification. Trevor founded Byers Amplifiers because he saw a need for amps that no one else is building. One of his amps is an original product, the Byers Model 10, while the other is a faithful re-creation of one of Leo’s earliest K&F amps — an amp so old and rare that the only way to see one is to make a pilgrimage to the Fullerton Museum in California. Byers has unique values regarding the way things should sound, feel and look. We interviewed Trevor at his shop in Corona, California to talk about Leo, the history of these old amps, and the new amps that bear his name.

Where did you get the idea to start an amp company?

It was the K&F that got me started. Working at Fender and knowing the entire lineage, including the K&F era, which is kind of separate, it was really intriguing to see what kind of things he came up with. Because it was so rare, the K&F was really appealing to me.

How did you discover this cool original gear while at Fender?

People would come in with things that were not in regular production and would want to have things done and have items reproduced, and people would come in for repairs too. It was a nice influx of cool equipment coming in, and we would turn around and reproduce it to the best of our ability. One of the first pieces we did while I was there was the “snake-head” Tele set, the first regular Fender-style guitar that Leo built.

Doesn’t that predate the Nocaster?

Yes, in fact I think that guitar was a ’47 or ’48. It had a four-piece pine Telecaster-style body, two inches thick with a small, black Bakelite pickguard, volume and tone control, and one bridge pickup. The snake-head headstock was the style he was using on his K&F lap steels, so it had three-on-aside tuners, with a solid, fat, maple neck with no truss rod — he hadn’t thought about a truss rod yet! They only made a few of them, and they were made as a set with the woody Pro amp.

So, did you put truss rods in the reproductions?

No, but they are big, round, C-shaped necks, and they’re quarter sawn, so they don’t move around too much.

There are actually guys who believe that necks without truss rods sound better.

This guitar is really neat-sounding because we used antique pine. One of my first jobs there was to rough-cut these old pine boards, glue them up, and plug and fill nail holes. Looking at these old-style guitars and amplifiers in comparison to what was being manufactured at the time, I saw a night and day difference. These have a style to them that nobody does any more.

This got me started thinking about K&F. If the circuit for the woody Pro was primitive, then the K&F amp circuit was even more so. The Pro had 6L6s and a push-pull output, and a 15″ speaker — a field coil speaker, which we had a lot of problems with. The K&F amps didn’t use field-coils and were permanent-magnet.

Give us a little background on K&F.

It was Doc Kauffman and Leo Fender. The information on K&F varies, so I can’t give a perfect history. They started around late 1944, and ran probably to the end of ’45 or early ’46, then they stopped making these in mid-1946. Leo had done some really interesting things — he had designed an automatic jukebox and little P.A. systems, and he was working with his radio company. Then, he had an idea for these guitars. He started making them and it became popular enough that he needed a larger investment; Doc didn’t think he could invest in something that looked like a hillbilly guitar, and at that time, that was the type of music played on them.

I remember even up until the 1960s, many jazz guitarists looked down their noses at these and told us, “When you grow up, you’ll get a real guitar,” meaning something more traditional, like a Gibson archtop.

Yeah, so Doc left and the K&F company was dissolved. Finding pieces from that time period is hard because there’s no record of how many were made and there were no advertisements for them. I do have some pictures from George Fullerton that Doc’s son gave him of the first piece that they put together, which is nothing like the ones that went into production. It’s very beautiful.

Did you get to play that original Tele that was copied for this run of instruments?

Oh, no. The story behind that guitar was that Leo was a huge stickler for not keeping prototypes around. There were two of those — the first one was cut up and the second was thrown in the trash. George pulled it out of the trash. He was young and had just started working with the company; he was a guitar player and this was his creation too! He and Leo went to little bars and shows and listened to players. Without telling them what they were up to, they asked the players what they would want in a guitar, which became the basis for their business and designs: being able to change small parts out easily and being able to easily change the neck on a guitar. There was a bit of a stigma attached to their early instruments because they weren’t craftsman pieces — they were functional instruments.

Yes, they were outside the instrument crafting tradition. This was a modernist piece of design, rather than following classical instrument-building traditions.

Exactly. So when I started researching all the K&Fs, I talked to George who was there just after Doc left, and I got as much information as I could from the closest source. Strangely, though they made guitars and amps in sets, many of the guitars still exist while most of the amps do not. I figure that the guitar is a functional piece and all you have to do is change the strings, but if you have an amp go out, it might have been easier to just go buy another amp.

Was it through the process of reproducing old gear, and speaking with George Fullerton, that you became interested in the 1940s K&F amp?

Yes, that amplifier in particular because it was so simple and because the circuit was kind of the predecessor to the Princeton, but instead of having an 8″ speaker like a Princeton, it had a big, large-magnet, alnico 20-30 watt 10″ speaker. This was late ’44 or early ’45, and these amplifiers were made from military surplus parts, so they were all different and had this unique industrial look about them. Design-wise, it wasn’t made to be the prettiest thing out there — it was made to be functional.

So it was just “The K&F Amplifier” and they only made the one model?

No, see that’s the thing, they made one, and we know the record shows from Doc’s writing on the pictures I have, that the first one they made was beautiful! It had wooden sides, a grille cloth that was embroidered with K&F on the front, and a 15″ speaker. The photo says, This is the first K&F [lap] steel, and this is the first amplifier in the U.S. with a hanging chassis and hanging tubes.” Before that, everything was put on the bottom of the amplifier and the tubes all sat up.

And that amp is gone now?

Yeah, in John Sprung’s book, Fender Amps: The First Fifty Years, he wrote that this amp was made as a custom, one-off piece, and it is likely gone now, since the only pictures we have ever seen of it were the from the 1940s.

That would be a fun one to reproduce, wouldn’t it?

Oh, it would be amazing. There was an article in the October 1998 issue of Guitar Player with a 15″ K&F — the style of the K&F that I am reproducing. It was the same cabinet shape, just larger, and it is the only time I have seen a 15 other than that one custom one-off piece.

So what you had was three or four amps, all without names or model numbers which were essentially prototypes

Yes, they were “if this works we will make another just like it” sort of deals. There were two basic models that you see in published pictures. One is the 8″model that looked like a little lunch box. It had one volume knob and one or two inputs, no pilot light, no fuse, and the cord coming straight out — that was it.

The other is the 10″ model, which is the one I’m reproducing. It had two inputs, no fuse, no pilot light, one tone control, and either one or two volume controls, and two channels — which was something completely new. Each channel ran on one half of the input tube, which is what Fender did until the Blackface era in the ’60s.

It’s not a large amp at only 5-6 watts. The speaker was an unknown Jensen model that had a large, plug-style alnico magnet instead of the horseshoe magnet. I am sure every example varied because the parts all varied — the knobs, transformers, everything. The transformer on the one I am reproducing was a replacement transformer right out of an Allied catalogue made by some unknown manufacturer.

How did you originally come in contact with the amp you decided to reproduce?

I worked with Geoff Fullerton at Fender, who became a good friend of mine. Geoff is George’s son, and was Leo’s personal assistant at G&L for several years. He was a builder and engineer there as well. George’s father used to work at Fender in the wood mill where he ran this huge ripsaw, which George, Geoff and I also ran, so I had become good friends with the family.

George is a wealth of information and a really interesting man to talk to. He has great ideas about how things were done, the reason things were done, and craftsmanship. Even though his guitars were not traditional, the craftsmanship that went into them was impressive. They case-hardened every single one of the screws that went into a guitar, so if you had to repair it, you wouldn’t strip out the threads. Nobody does that kind of thing anymore because it is not cost-effective.

When I talked to George about the amp, he told me about one at the Fullerton Museum owned by Phyllis Fender, Leo’s widow. As he described the amp to me, I decided I wanted to take a look at it. Phyllis said sure, so they pulled it out of the museum for a day. I looked at it, taking every picture and measurement I possibly could. I worked with what I had, but it wasn’t enough to do a reproduction. Later on I was able to go back, and they let me take the chassis down and measure every single component. One thing I couldn’t do was turn it on.

You were able to disassemble this old amp down to the component level?

I was. I took my meters down there and measured everything. Not only did I measure it, but I cross-referenced it to the color code because those resistors and capacitors are 63 years old now and have drifted a lot. One of the things I noticed is that he used many of the components because they were the only things he could get. They weren’t exactly the right value for the position they were in, but he put them in there because they were close enough and that’s what he had.

So, I’m looking at it, and George leans over and says, “You know, you’re the first person who touched the inside of that amp since Leo; you’d better be careful!” Because no one had touched it in all those years, the chassis, being made of steel and zinc plated, was pretty much pure white and powdery — I wasn’t about to leave my fingerprints in it!

Are you going to reproduce the zinc plating and everything?

Oh yeah, but I’m not going to relic it or try to make it look old.

Are there any ground issues getting through the zinc?

Yes, you have to grind away the zinc to get to the steel. And that was one of the things; there’s no circuit board, it’s all point to point, and whatever had to be grounded was run straight to the chassis right there. It was function over form.

What year was the original produced?

I don’t really know if it is one of the earlier or later ones, although I think it is earlier. There is a kind of complex cutaway on the top of the amplifier and a relief on the cord panel that is pretty much decorative. Those two things are also on the 15″ amps that we know were the first ones made. Later examples don’t have either of those features on them, so it is likely an early piece.

Did your experiences at Fender and taking apart the old K&F amp lead to your decision to start an amplifier company?

The K&F thing led directly to my own amplifiers. That amp was amazing and cool, but it was so rudimentary. Boutique amplifiers are becoming a bigger business now and I though it would be interesting to see if I could do my own interpretation of the design.

I was looking at all these beautiful Fender guitars that we were making, the amazing Custom Shop guitars with custom finishes that people wait years for. There are some really nice-looking amplifiers out there, but most of them look like big Tolex suitcases.

It all started me thinking about something that was small enough that you wouldn’t worry about it getting banged around, with the form plus the function, and replicating some of the beauty of the guitar finishes. That really appealed to me – no one was doing that. Finishing it like a guitar, the correct way, is such an art. I wanted to make them so they would match people’s prized instruments.

Over the years, guitars and their finishes have gotten more elaborate, but you aren’t doing that with the new Model 10; it is using simple shape, texture and color for the amplifier, rather than the busy style of many expensive guitars.

I started out spending hours designing cabinets, and the right one just hits you. This one was simple; it effectively gave room for my logo, but with some different elements. I have 1″ radiuses on the corners instead of ¾”, which makes the amp look more spherical, instead of looking like a big square

It gives it a softer, more attractive appearance.

I started the design of the amp with the cabinet, and I got that nice angled swoop to the front, which was simple, not complex — you see some of the amps from the 1940s that had great grilles on them, and some were so complex. Once I got the design for the cabinet down, and I knew that I could physically produce it from a woodworking standpoint, I knew how much space I had, so I could work on the chassis and circuit layout.

Tell me about the Model 10’s circuit and electronic design, and the sounds you were going for.

Well, George introduced me to Bill Sterle who started working at Fender around 1960. Bill is an audio engineer who designed a lot of the original Blackface amps.

Having someone who was there and who designed amps telling me why they made certain decisions is so much different than starting with copies of what Fender, Gibson, or Marshall did. I learned distinction between the amps Bill made and the Fender amps of the 1950s, which were the easiest and simplest designs. The Blackface-era amps were much more complex designs and they were really trying to do different things with the preamps to keep them cleaner.

When Bill was designing things, he stressed that distortion is your enemy — that’s the school of amp design he came from. You have to have the cleanest representation possible. I went to Bill’s house for hours and he would describe everything from tube heater circuit design to what you want to get accomplished in the preamp section, the phase inverter section, and the power section. He told me once you get going on the tone controls, you can go crazy because there are so many variations in tone circuits — not only what you use, but where they are placed.

I wanted to have a 10″ speaker in there. A 10 just has a clarity that you cannot get from an 8″ speaker, and I didn’t want to go as big as a 12. 10s have a really neat sound to them if you find the right one. I knew it was going to be either a small, single-ended design or a cramped, push-pull design. I ended up starting off with a small single-ended design.

So, design wise, you met some of the original guys who developed modern guitar amps, and took it from there, as if you were in that era.

Oh yeah, and every single element that was put in the amp was based on what I was trying to accomplish in the circuit, not based on something I was trying to copy. My initial intention was to make it really straight and clean, without a ton of bells and whistles. It is a single-ended design with a 6V6 power section and a 12AX7 preamp tube.

I looked at a lot of Internet message boards for guys who are building amps, and for players in general, to find out what kind of modifications they were making and what they wanted out of an amp. I tried to keep it really simple and clean, but I did put in a few things that I thought would expand the tone a little more.

Is there a tube rectifier?

No tube rectifier in this. In such a small, single-ended amp that putting one in would be more of a novelty than anything functional. Not putting one in allowed me to use a smaller power transformer and to clean up the power and make it more stable, along with giving me more space to do other things in the chassis. Also, when I went back and talked to Bill Sterle, he threw his hands up and said, “Tube rectifiers are absolutely worthless!” [Laughs]

My impression is that stout, well-built power supplies produce robust tones, especially at high levels. When you are pushing the amp, and you’re not clobbering the power supply, the amp doesn’t freak out as much. If I want a little sag and compression, I use a compressor!

Well, yeah. It’s all relative though, because there is a ratio between the voltage and the current that the plates see. You push harder, sand the plates, and try to draw more current. If the current isn’t there, then there is going to be a difference in the tone.

I started with a solid-state rectifier and that is the only solid-state piece in the amp. In the preamp, I used more of a Blackface preamp design, where I split the 12AX7 in the middle because the amp only has one channel. I do have two inputs on the amp, but one is just hotter than the other.

So there are only two tubes in the amp?

Only two! It’s simple — there is just a treble and a bass control. With all passive tone controls, if you use the control, there is a certain amount of insertion loss, so on bass control I put a switch so you could remove the tone controls from the circuit completely.

The Model 10 has the standard volume, bass and treble controls; then there is the switch. What does it do?

It takes out the negative feedback loop. You turn that off and bypass the tone controls and it will crunch just like an early tweed Champ. Even with only two tubes and three knobs I wanted to be able to have a range so it isn’t just for one style of play; it is an amp that you can play around with and get a cool tone out of.

It has an amazing array of tones for having so few controls.

I have designs of every shape and size, but this is where I wanted to start. In the larger models, I am going to do a 15-20 watt amp, and I may do as much as a 30-35 watt one as well, though I don’t want to come out with a 100 watt monster.

I think people are starting to re-evaluate how much wattage is really needed.

You know, one of the many helpful things I learned from Bill Sterle was how to test everything correctly. Lots of amp makers out there will say, “This is a 5-watt amp,” and that’s what they assume because a similar one was made by Fender, but Fender tested where the wattage comes up just before distortion, on every one, and that’s how we test as well.

The Model 10 puts out almost exactly 5 watts. It has a cathode bias power section and I go through and measure every single one of those tubes and every single output section of each amp to make sure it is right for this design. I don’t want to run these as hot as I possibly can to get every last watt out of them, because it is hard on tubes. I offer NOS tubes as an upgrade, and they are not making any more of them! I run them right in the middle where you get great tone and good longevity.

What tubes have you been using?

Right now I am using Electro-Harmonix preamp tubes and JJ power tubes. I think the JJ 6V6 is a really neat tube. They can handle a lot of plate current, and they sound good.

If somebody wants a Model 10, how long would it take?

I have all of the parts ready to go, but I have a six to eight week lead time on the custom-colored cabinets, including shipping. It takes about four weeks for the paint to be completely finished, because it has to be perfect. It is a guitar finish on the Model 10 and it’s done just like any expensive guitar finish. The amps are built to order, though I may stock certain colors here and there.

It’s exciting to see the founding of a company with such an amazing product. Do you have a price set for the Model 10?

It looks like the Model 10 will be $1050, at least as an initial release price.

You spoke earlier of having several color choices and perhaps some clear finishes on nice wood available.

The cabinets right now are poplar for the solid colors, and ash or alder depending on whether the finish is a blonde or sunburst one, just like a guitar.

If someone asked you what your amp sounds like, what would you say?

Well, what I was trying to achieve was a combination of the tweed Champ and Princeton, combined with a Blackface Champ and Princeton. I wanted to be able to combine all four of those amps together so you could get a really grungy, overdriven, tweed tone or a really clean, clear tone with or without tone controls.

Tell me about the K&F reproduction amp, is that currently in the pipeline?

That amp is 99% done. Because this amp has never been done before, and because the parts are not off-the-shelf parts, everything is different from what is currently available. Everything had to be done from scratch; transformers had to be custom wound, and chassis had to be custom made — and the chassis are not normal dimensions by any means. The tubes are all NOS tubes, because there is no current equivalent to them.

It’s an octal socket preamp tube isn’t it — a large base and pins like a power tube? What tube is that?

It’s a 6SC7 medium mu triode and a 6J5 triode in the preamp section. Each channel gets half of that triode. It’s a pretty low-gain tube actually; it’s not overdriving the preamp circuit a lot like the later 12AX7s often do. There is also a 5Y3 rectifier and a 6V6 output tube. Both input signals merge into a 6J5. Instead of putting one channel with one preamp tube, he made two channels that merged into one preamp tube. There’s one volume control for both channels. The circuit is a lot different than a modern amplifier. Leo was doing it to see if it would be functional, and it was very rudimentary and basic.

The octal preamp tubes give a really unique sound to the amp. They don’t drive it very hard, but it does put out a pretty thunderous crunch when you want. I am keeping it as historically correct as I can, with carbon comp resistors, Mallory 150s as the tone caps, and all cloth-covered wiring, which I don’t do in the Model 10. I am not trying to reproduce a look in the Model 10, but am going for the best possible sound, so I’m using all the best components and wiring by today’s standards.

You selected the components for the Model 10 by listening to them, didn’t you?

Yes, but the K&F is a little different. It’s not wired like you would wire something today; it has series heaters, so you get that hum in there that makes for a unique sound. The only changes I made were necessary for safety. Of course, there is a fuse in this one, along with a 3-prong AC plug. Other than that, it is rudimentary in every way. The tube sockets are spot-welded to the chassis.

Did you actually replicate the spot welds?

Oh yeah! Lots of guys would have riveted the sockets in place, but that was an extra expense, so they spot welded them.

It probably had a terrific ground connection.

It does. I found an original output transformer and power transformer and had Mercury Magnetics reproduce them for me. The speaker was a 10″ Alnico plug-style speaker rated at 40 watts for a 5-watt amp, so it was way over-engineered for the circuit. Most Alnico speakers have a horseshoe shaped magnet, but this one has 2½” donut-shaped magnet. It was also used for higher-end audio and larger-wattage amps. It makes for a really heavy speaker, but it’s really neat. This Weber is the closest to the original speaker that is available.

How much is the K&F reproduction amp going to cost, and when will it be available?

I’m trying so hard to get it finished! I am talking to a paint manufacturer about the wrinkle paint we need, and if that works out we’re in business with getting the K&F out. We should be ready in October at the latest, and the cost will be about $1000.

Playing the Amps

I brought my 1987 hardtail Tom Anderson to Byers‘ shop where I got to play through the first Model 10 off the line and a K&F reproduction prototype. Here is a sample of what I heard:

Model 10

The Model 10 is a beautiful amplifier. If your favorite custom guitar builder built an amp, it would look just like this.

The Model 10 is clear and detailed in the way that only minimal circuit paths can be. Set clean, with the tone controls engaged and the feedback loop in, the highs and lows are well-balanced, the tone circuits do what you wish they would, and the result is a sound that makes you want to play more. Turn off the feedback loop and things get woollier and more tweed-like. Switch off the tone controls and the amp gets a more aggressive, throaty attitude going.

K&F Reproduction

The K&F reproduction amp is totally different from the Model 10 and totally different from almost anything I have ever heard. I can almost hear Charlie Christian playing one and I suspect that today’s players will find musical uses for this tone. The K&F reproduction is very big and a bit wooly-sounding, yet not muffled or dull at all. It gets pretty powerful sounding when you push it hard.

Source: https://mercurymagnetics.com/pages/news/PremierGuitar/PremierG-10.htm

ToneClone – Tonelux transformers

It’s no secret to any of us that Fender’s Deluxe Reverb has long been considered the guitar player’s ultimate desert island amp. It’s lightweight, compact, incredibly sturdy and dependable, and it captures the essence of classic ’60s Fender tone. Blackface models built between 1964 and 1967 can cost as much today as a clean vintage Super Reverb, and Silverface Deluxe reverb amps built from 1968 through the mid ’70s remain a bargain, selling for $600-$900. There is very little difference between unmodified amps built during the two eras, except for a couple of caps connecting the output tube grids to ground in the Silverface amps, and a variety of stock speakers, including JensenCTS and Oxford. There is absolutely no reason why a Silverface Deluxe Reverb can’t sound every bit as wonderful as any Blackface amp, and some of the Silverface amps will sound better than some Blackface Deluxe’s you’ll find. Local amp wizard and advisory board member Jeff Bakos has observed that some of the exceptional Deluxe Reverb amps he’s heard (and he’s heard hundreds of Deluxes) seem to have “hotter” power transformers, and the slight inconsistencies in the way some transformers were wound can make a big difference in tone. Earlier today we heard as much in Jeff’s shop in a ’66. Unfortunately, it all comes down to the luck of the draw when finding those special amps. If there is fault to be found with the sound of a Deluxe Reverb (and it really isn’t a fault), it’s the speed at which the amps begin to break up. The clean threshold of the Deluxe is pretty low, and while this characteristic feature is an irresistible attribute to many players, we wondered what could be done to make the Deluxe Reverb even more versatile without losing its unmistakable tone. The modifications we describe here are very simple as modifications go, and all of them are easily reversible. We encourage you to try some and let us know how you like the results.

We started with a beautifully preserved ’68 Deluxe Reverb acquired on eBay for $900.00. The owner had replaced the original particleboard baffle board with pine, recovered it in vintage Blackface-era grill cloth, and installed a repro Blackface plate. We also received the original baffle board covered with the original blue and silver grill cloth, the aluminum trim, and the Silver face plate. We had acquired a replacement output transformer from Mercury Magnetics, and although the original transformer seemed to be working fine, we wanted to see what we might hear by swapping transformers. The Mercury ToneClone series transformers is the result of years of testing in which Mercury blueprinted some of the best sounding output transformers that could be found in vintage amps and painstakingly reproduced them in every detail. At first, the new transformer didn’t sound starkly different from the original – it sounded exactly like the original. But over time, it became increasingly apparent that the amp was behaving with more dynamic response. Notes and chords were imaging differently than before. Individual notes within chords were better defined, the amp responded faster to touch, and harmonics were more pronounced and complex. We’re the first to subscribe to the “don’t fix it if it ain’t broke” school of amp maintenance, but in this instance, the fix was a good one.

One of the easiest things you can do to Deluxe Reverb amps is rebias them for 6L6 power tubes. The outcome is predictable and sublime — more power, more headroom and better lows that won’t fall apart. Call it the “Beano”” treatment for your farting DeluxeJeff Bakos rebiased the amp after we had installed a pair of RCA black plate 6L6s, and we were mighty pleased with the results. You lose some of the compression and darker character of the 6V6 tube when you switch to 6L6s, but there is very little downside to the trade off — just big, bloomy 6L6 tone, and lots of it.

After installing the RCA 6L6s, we opted for an NOS RCA 5751 rather than the 12AX7 in V2, and it really smoothed out the tone to silky perfection. We also experimented with a Chinese 5AR4 rectifier tube, a new Sovtek 5AR4 and a Mullard 5V4. The Mullard pulled the volume back down ever so slightly, but it also seemed to sweeten the tone, rendering a throaty voice that fell nicely in between the “old”” amp with the 6V6s and the “new” one with the 6L6s. Either tube is a good choice — you’ll just have to decide which sound you prefer. Among the 5AR4s, we actually preferred the sound of the Chinese tube over the Sovtek, although the Chinese 5AR4s aren’t quite as robust. Our Deluxe came with an absolutely dreadful (recone?) non-original Fender “blue label” Oxford ceramic magnet speaker that was commonly used in the BassmanTwin and Pro Reverb. We replaced it with n Eminence Legend V12, and this speaker turned out to be a “best buy.” The V12 features a British cone, and the tone is extremely round, well-balanced, and warmer than the Jensen C12N. It’s rated at 80W, and as usual with Eminence products, value and tone are absolutely unmatched for a speaker that sells for under $50.00. Jeff also likes the Legend 125, which is rated at 50W and built with a 1.5 inch voice coil and a slightly lighter magnet. As we observed in Eminence founder Bob Gault’s interview, the low price of an Eminence speaker is no indication of cheap construction or tone. The speakers rock, and they are voiced to appeal to a wide variety of players. We continued experimenting, and our next choice was a new Jensen C12K. We had seen this speaker in Victoria and Fender Twins, and it’s a massive thing. Built in Italy, and rated at 100W with a 2 inch voice coil and 50 oz. magnet. The C12K in a Deluxe with 6L6s yielded huge clean tone from top to bottom, with more high frequency emphasis than the Eminence speakers, and no speaker distortion whatsoever. The Jensen C12K in a Deluxe won’t be everybody’s idea of the perfect match, but it you crave a wide-open, big sound with nothing but clean speaker, the Jensen is a worthy contender at $90 retail. The last speaker we installed was a paper (not hemp) Tone Tubby from A Brown Soun. The paper-cone Tone Tubby is voiced a little brighter than the hemp cones, and we were floored by its rich, smooth character and charm. Jeff described it as being “silky smooth,” and just what he expected, with great lows, stout midrange, and creamy, creamy highs. Now, do you really need a $200 speaker to sound great? Of course not, and the price of a Tone Tubby is not for everyone. But if it’s the speaker for you, you won’t rest until you get one, and nothing we’ve heard can touch it. Enjoy yours, Eric, and enjoy milking some more of the good thang out of your Deluxe, gang. Hey… if not now, when?

 

Which Guitar Amp to Buy

Ten years after our first published amp review (the blackface Vibrolux Reverb), we still find ourselves answering readers’ questions about which amp to buy. We’re not complaining… your subscription to TQR has always included phone or email access for those contemplating a new gear purchase, but it seems that published reviews can still sometimes prompt more questions than answers. We understand, and like you, we are routinely faced with these same buying decisions just about every month as we look ahead to future issues. “Power” and “headroom” (or lack of it) seem to remain among the most daunting considerations for prospective amp buyers. This may not keep you up at night if you’re looking for a toneful box to play solely at home, but the range of clean and overdriven tones available from a single amplifier that can hang with a band is absolutely critical – the tipping point for guitarists who wish to have both clean and grittier tones available on the fly. And even the casual “bedroom” player (does anyone really play their guitars in the bedroom?) will quickly discover that big, lush guitar tones – clean or jacked into rich distortion – are often best obtained through a “bigger” amp. We’re not suggesting that we don’t love our ’58 tweed Tremolux or ’64 Deluxe – they both uniquely, timelessly epitomize great guitar tones – but an entirely different realm exists within the range of vintage Fender amps, and try as we might, we have never found another amplifier quite as versatile, user-friendly or uniquely toneful as the blackface (1965–7) 40 watt Pro Reverb – still the most under-valued and overlooked reverb amp from the entire blackface era, although aside from its 2×12 speaker configuration, the Pro is nearly identical to the Vibrolux and the Super Reverb amps.

Yes, the 2×12 Pro Reverb can move some air, just as an AC30or Matchless DC30, both highly coveted amps for good reason, do the same. Experienced in a room, 2×12 amps produce an ambient presence and a spatial quality that single 12s can’t match. That extra speaker isn’t adding volume as much as it simply disperse sound effectively by filling more space. And although the Pro Reverb is rated at 40 watts, the smaller output transformer Leo Fender chose to use delivers only 28 watts, probably in an effort to minimize speaker failure, yet the original Oxford and Jensen 12 s shipped in the Pro still blew when pushed by enthusiastic rockers. A well-maintained Pro Reverb will typically produce classically clean Fender tones with strong bass and treble and slightly diminished mids from “2” on the volume control to “5,” gradually spilling into lush Fendery distortion at higher settings. If you choose to use an overdrive device to achieve distortion at lower volume levels, the Pro will sound significantly better than most 20 watt amps because your pedal is affecting a cleaner signal, rather than adding distortion to an amp already spilling over into distortion. And as we have reported so often in the past, non-invasive and completely reversible modifications can be made, such as the addition of a 25K mid range pot utilizing the existing back panel hole for the extension speaker jack. This single mod enables the Pro to develop a very ballsy British voice as midrange is increased, while completely preserving the integrity of the original Fullerton tone with the midrange pot set at zero, rendering two outstanding amps in one. Intrigued? You should be, because we have never heard a contemporary boutique 2×12 combo amp that can approach the sound of a Pro Reverb equipped with a solid set of tubes and speakers. And with the range of speaker options available today, you can effectively custom design and shape the sound of your Pro for more of a traditional, bright“American” sound, a heavier or chimier British tone, or the two combined.

Ah, but buying old amps is risky business says you… what if I get a “dog” or it needs a lot of work? I’d rather buy some-thing new and not deal with the unknown. Fine, do that. But for those willing to reap the rewards that only a certain degree of risk can offer, it’s not that difficult to minimize your chances for disappointment. Here’s how:

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British Tone in an Amplifier

Following up on the successful introduction of 65 Amps’ flagship London 18W, the company has launched its second model — the Marquee. Named for the legendary Soho music venue where every ’60s British band of note once honed their craft, the Marquee is a bigger-sounding, louder version of the London 65 in some respects, endowed with great headroom and presence. We asked co-founder of 65 Amps and Sheryl Crow guitarist Peter Stroud to describe the musical intention of the Marquee, and our review follows….

TQR: What inspired the development and design of the Marquee, Peter? What did you want to accomplish specifically?

Peter Stroud: We had guitarists loving the sound of the London, but still needing either more volume or clean headroom. Personally, I wanted an amp to replace the Super Reverb in my live rig with that Fender clarity, but more of the openness and touch sensitivity of an amp like the London. Our initial idea with the Marquee was to create a more powerful version of the London 18 watter using 4 EL84s. But we also wanted something with the midrange clarity of the British amps and the clean sparkle of the American Fender Blackface sounds — just not as hard sounding as the 6L6 cleaner tone can be. On top of that, it has a higher gain tone that really roars.

TQR: To what extent were some of the design features in the Marquee such as the cascaded twin-triode operating in pentode mode and the 6-way Color control inspired by vintage amp designs?

Peter Stroud: Our initial intention for the Cascode (note spelling) configuration in this amp was to find a sound similar to the pentode type EF86 tube we use in the London, but more quiet. Due to vibration and noise issues inherent with EF86 tubes, we were apprehensive using it in a higher powered combo. The cascode circuit, which utilizes a 12AX7, was popular in early hi-fi preamplifiers. It has a harmonic content similar to the pentode circuit but produces more even-order harmonics. Randall Aiken helped us greatly with this circuit and we’ve continuously tweaked it’s current configuration in our amp. The end result is a distinctly different sounding channel from the Treble-Mid-Bass channel — very warm and rich sounding. It sounds beautiful with single coils and 12-string electrics. So, the Marquee initially came from many inspirations. Dan (Boul) and I are big fans of the Selmer amps. A few years ago while on tour in the UK I had picked up a Selmer Treble & Bass 50 MkIII, which is the early ’70s silver metal front — the ugly one. But that amp sounds awesome, like a “British Fender Blackface” with two EL34s. We’ve since found a Mk I Treble ‘n Bass from the first year they were built.

The font end of the Marquee Treble-Mid-Bass channel was initially inspired by the Selmer, but it branched off quite a bit. We just aimed for that sound. There are also similarities with the Selmer front-end circuit and the early ’60s brown-Tolex Fenders. I know one of your favorite amps is that killer Vibrolux 1×12 you have. The (Marquee) power stage is a fairly typical British-style 4-EL84 circuit. From there we spent months tweaking the tone circuit. We wanted the Treble-Mid-Bass tone configuration for more control with a higher powered amp.

TQR: You’ve played just about every conceivable guitar amp and for years your rig consisted of a Super Reverb and Marshall 50W. To what extent does the Marquee succeed in giving you both the clean and overdriven tones you need at usable state volumes, and how do you use it specifically?

Peter Stroud: On the latest tour I used both a London and a Marquee and A/B’d between the two. The two together worked perfectly for our stage volume. I’d set the London for a slightly driven rhythm sound playing through an EF86 channel and would use the gain boost for leads. The Marquee took the place of my Super Reverb as my clean sound, and it proved to be better since the mids are more pronounced and you get the nice dynamic saturation of EL84s. It’s much more touch sensitive, which is hard to get with a clean sound without using a compressor. The only time I’d kick on both amps was for Led Zep’s “Rock N Roll,” which we play as an encore. I’d crank the Marquee to 6, hit the gain boost and boost the mids. It totally hit the “Pagey” kind of sound. You can dump the mids and boost the bass and highs and get a chimey sparkling clean tone — settings around 4 on the volume, treble and bass around 6 to 7 and midrange around 4. For a cranking rhythm I’ll set the volume around6, boost the mids to 8 or so, drop the bass around 4, treble at 5. There’s also a footswitchable gain, like on the London, so you can set a rhythm tone on the T-M-B channel and kick in the boost for lead. If you turn the amp up to 10, look out!

TQR: You mention “mustard” caps on your web site being used throughout the amp — are these modern reproductions of the original “mustard” caps used by Marshall in the ’60s?

Peter Stroud: Yes, we use the SOZO caps made by John Gaynor. John’s a Marshall enthusiast who has totally nailed (and surpassed, in our opinion) the “mustard cap” tone where you get the nice smooth mids and bell-tone clarity.

TQR: What else are you working on?

Peter Stroud: We have two new models in the works — a smaller “grab n go” 1×12 combo which actually incorporates a master volume with two EL84s. It has a great sounding master volume that has a sound of its own that can be disengaged so that the amp ha a non-master function. Sort of a “British Fender” vibe again. The thing screams, it can get chimey clean, and it’s incredibly versatile. And over the past six months, we’ve been developing a KT77 head using our Marquee as the springboard with a KT77/EL34 power stage. We had a handful of pro level artists who wanted extreme volume and headroom, where they were used to their 50 and 100 watt EL34 hears and quite a lot of volume. Plus, Dan is a big fan of the Vox AC50 and I’m the Marshall fanatic, so we got into that mindset again. We sent a prototype out for a test run with Rich Robinson of The Black Crowes and he ended up using it as his main amp for the entire last month or so of their tour. When we got it back, all the knobs were dimed. Couldn’t ask for better testing in the field! We’ll introduce both of these amps at Winter NAMM.

REVIEW — 65 Marquee

We spent a lot of quality time with the 35W Marquee Club, and it impressed us as a feisty chameleon that can gracefully move between big, jangly clean tones and an impressive roar with a deep palette of voices available from two very different input channels.

EL84 amps typically produce a distinct, musical compression characteristic that is absent in amplifiers using 6L6 output tubes, yet the Marquee produces gobs of clean headroom — albeit British headroom rather than the trademark 6L6-fueled fidelity of a Fender amp like the Twin or Super Reverb. As far as we’re concerned, British tone in an amplifier denotes rich harmonic depth and chime, often augmented with a dominant midrange emphasis, while Fender amps (Blackface models in particular, sound scooped in the mids by comparison with a wider, broader, looser feel and toner not unlike the difference between the sound of oooh and ahhh. In the Marquee, individual strings seem “closer together,” yet still well-defined throughout its range of clean settings. EQ coloration is accomplished in the “Classic” Channel bass/mid/treble/cut controls, and in the “Normal Channel via six EQ presets on a rotary switch. This “color switch” progressively thickens tone with gradual increases in lows and mids, but the Marquee’s chime and sparkle remain audibly preserved in every setting.

The Marquee produces moderate levels of smooth, overdriven tone at higher volume settings (+6) in the Normal Channel that can be neatly managed from the volume on your guitar, while the footswitchable Boost feature in the Classic Channel yields scorching distortion and sustain that nearly rival that of a Marshall JCM 900 Series Mk III. However, the Marquee delivers a chimier crunch rather than the more linear and cutting, laser beam focus of a high-gain Marshall. It’s a prettier brand of mayhem, if you will. And unlike many vintage British amps, the Marquee succeeds in delivery an enhanced range of both clean and overdriven tones, as well as a more versatile and varied range of EQ emphasis. Overall, we found it to be an inherently bright amp with the EQ controls in neutral settings, but you are also given plenty of room to shape the voice of the Marquee, from brilliant and clangy, to thick, heavy and imposing. We had no trouble dialing in great tones with all of our guitars — thickening the Teles and Stratocasters, planting a wet kiss of treble emphasis on the humbucking Gibsons, and alternatively mining the jangly clean chime and perfect meltdown of P90s. A potent rock amp that can cover a lot of ground, the Marquee is handwired with point-to-point construction that meets the high standards we have all come to expect from custom builders today, the transformers are custom-made by Mercury Magnetics, and the fit and finish of the cabinet work were flawless. As the name implies, the Marquee is steeped in the tones that defined modern rock & roll, viewed through a properly British perspective. And as Fender’s Ritchie Fliegler is fond of saying, “If this is what you like, you’ll really love this!” Quest forth, mate.

Source: https://mercurymagnetics.com/pages/news/ToneQuest/_2007/TQRJan07-2.htm

Benefits of the Power Transformer

Mercury Magnetics

As I mentioned earlier in the article, I had not originally intended to use a Mercury Magnetics power transformer (PT), electing instead to save a little money and use the stock DRRI PT. I’ve since changed my mind. How this came to be makes for an interesting story.

About 10 days before I was scheduled to pick up my amp at Mikey’s shop, I sent out emails to all the companies that I linked in this article. This included Mercury Magnetics since Mikey was putting their output transformer, reverb transformer and choke in my amp. Shortly after sending out an email to Mercury, I heard back from Paul Patronete who graciously gave the OK to link to their site. He also took a moment to let me know in addition to the other Mercury iron I was using, their power transformer would make an improvement in the tone of my amp. Paul invited Mikey and me to give Sergio Hamernik (an owner of Mercury Magnetics) a call to discuss the benefits of the power transformer.

I really appreciated the helpful suggestion but I hadn’t ever heard of a PT making a difference in tone, thinking the other pieces of Mercury iron would make 90% of the improvement. I did let Paul know I’d add a comment in this article saying I’d heard from Mercury and the PT would make a big improvement in the tone. He wrote me back with an interesting bit of information I had never considered. Here’s a paraphrase from the email he sent me:

The stock reissue PT does an OK job of supplying the required voltages to the circuit however the overall PT’s behavior under working conditions is not the same as the original vintage Deluxe Reverb PT. Characteristics that make the reissue PT different than the original PT involve flux density, AC regulation and primary inductance. These characteristics are a very important factor for the player that wants to nail the tonality of the vintage Blackface Deluxe Reverb amp.

Paul once again encouraged me to talk to Sergio. This certainly piqued my interest so I got in touch with Mikey and discussed Paul’s comments. We decided to get Paul on a conference call and to also see if we could speak to Sergio. We called Mercury in the late afternoon, four days before I was due to pick up my amp. Although Sergio wasn’t in, Paul spent almost 1.5 hours talking with Mikey and me about their power transformer and the rest of their iron.

Paul is a guitar player first and foremost and his enthusiasm for great tone is infectious. In addition to talking about all the good things Mercury Magnetics has brought to the industry and guitar players, he talked about what some of the cutting edge builders are doing. Mikey and Paul had very similar opinions on what makes great tone and why. It was a very informative and fun conversation. At the end of it, I certainly wanted to speak to Sergio so Paul invited Mikey and I to call again in the morning.

The next day, Mikey and I called Paul and after a brief chat, he brought Sergio to the phone. It was truly a treat to talk with Sergio and I learned a LOT about tube amps, the importance of an amp’s magnetics (the iron) and primarily, the benefits of using a Mercury Magnetics power transformer engineered for a Deluxe Reverb. As we talked, I jotted down as many notes as I could manage. I’ll share them with you now, although please keep in mind I may not have captured everything Sergio was conveying. He did a fine job though of keeping his information geared to my level of understanding.

Sergio started by asking me if I knew what modulation is. Of course I’ve heard the word but I wasn’t sure what it meant in relation to tube amps. He explained that an amplifier is a modulated power supply whereby the guitar signal is used to modulate the amp and so the quality of the power transformer affects tonality. He said the power transformer (along with the rectifier tube, a 5AR4 type) is responsible for taking the AC wall current and transforming it into the DC current used in certain parts of the amplifier. He said the power supply sets everything else up and everything depends on the character of the power supply. For example, since it helps determine the AC and DC voltages going to each section of the amp and tubes, it has a big impact on the feel of the amp.

I learned that although the stock DRRI power transformer provides the right amount of volts and amps (current) to the amplifier, the DRRI power transformer is nothing like one of the original PT’s used in Deluxe ReverbsSergio said among other things, the flux density and primary inductance all have to be right. As a comparison, the DRRI stock power transformer has 1/2 or less inductance on the primary than a Mercury Axiom PT. (You may recall from a previous section; inductance is the opposition to changes in current.)

He said capacitance and leakage reactance are critically important and Mercury Magnetics power transformers have lower flux density and heavier iron with better permeability. Capacitance and leakage reactance between the windings, and where the filaments are in relation to the B+ supply, really matters. Now that’s a mouthful! I think I’ll need to spend some time researching the concepts mentioned in just the last two paragraphs so I can better understand the electrical theory behind his designs. One of the best things about this project and writing this article is being exposed to new concepts. This is my idea of fun!

Sergio did break this theory down into practical examples for me. He explained the Mercury Magnetics method starts with finding the very best sounding amps and examining their iron. For example, if there is a great tone on a recording, Sergio can try to find the exact amp used on the recording and use it as the model for new iron.

 

Mercury Magnetics’ Axiom power transformer for a Deluxe Reverb (not for a DRRI)

The DRRI power transformer has different physical dimensions than the one in a Blackface Deluxe ReverbMikey has an electronic caliper that does very precise measurements so he sent these dimensions to Paul so Mercury can provide the perfect power transformer for this amp. They have the know-how to build power transformers that will sound just like one in a Blackface Deluxe Reverb. They do this by using the very best example of an original 1965 Deluxe Reverb transformer, unwinding it and laboriously documenting every nuance of how it is constructed. Then a combination of old and new technologies is used to create the very best transformer possible.

There’s a reason why guitar players seek out older amps, and this obviously is because of better tone, which I’ve come to understand is largely due to quality magnetics. I learned the magnetics available to amp builders in the 50s and 60s were made from materials optimized for the military for WWII and the Korean War. There was a tremendous overstock from the military build-up and amp builders had ready access to very high quality materials.

Modern materials are designed to be cheaper to hit price points. Sergio told us he specs custom steel to make Mercury transformers. They do enough volume of business that he can insist his steel manufacturer hand crank the steel through a gas oven, just like it was done in the 50s and 60s. Steel and copper behave differently at different milliamps so the properties of the metal must be designed and manufactured to this end. For the guitar player, this level of quality shows up in things like the ramp rate of note attack, the feel of the pick attack and better bass note response. He also used the choke as an example, where the Q-Factor (the measure of quality in a resonance system) is quite a bit different between the stock DRRI choke and the Mercury choke, so much so that it makes for an audible difference.

Sergio explained the power transformer is rated for a lot more watts than the amp produces. For example, the Mercury Magnetics Axiom power transformer for my amp will be rated at 120 watts and is capable of supporting an audio output of up to 60 watts. The general rule-of-thumb is the power transformer needs to be rated at twice as much as the maximum audio output.

Since this power transformer has specs well in excess of what the two 6V6 tubes are capable of creating, it can safely run 6L6 tubes. 6V6 tubes require only 60% of the power of 6L6 tubes. The output transformer is also capable of handling 6L6 tubes so by getting the Mercury Magnetics power transformer, I can get more power and a different tonality out of my amp than with the 6V6’s. This is a nice bonus and one I hadn’t considered when Paul first emailed me, suggesting their PT. I prefer 6V6’s in the amp but it’s nice to have another option.

Mikey asked Sergio to describe the sonic differences we might expect with the use of the Mercury Axiom reverb transformer. Sergio said the sound differences are subtle because it is such low power but if you have good ears, you’ll hear differences in “evident detail” and a “perceived wider bandwidth.”

Mikey and Sergio talked a bit about the dramatic effects of using the Mercury output transformer. Sergio likened his output transformers to a window with no glass and no screen, allowing all of the tonality of previous sections of the amp to pass through with great clarity. He explained the excellent “phase relationship tonality” (perceived as a 3 dimensional swirl) is dependent on the quality of the construction of the transformer. By comparison, the DRRI output transformer acts as dirty glass covered by a dirty screen. I couldn’t help but be reminded of the scene from the movie “My Cousin Vinny” where Vincent Gambini (Joe Pesci) disproved the testimony of a witness by pointing out with pictures how the witness was looking through dirty glass, a bug covered screen, and through trees and bushes at a fleeing car.

As a tube amp enthusiast, I’ve been reading and learning about tube amp electronics for quite some time. In this conversation with Sergio I learned a lot of things I had never considered. Of course, by now I was completely convinced their power transformer should go in my amp! You can understand why the top amp builders call upon Sergio for his expertise, designs and remarkable archive of information.

If you take a look at the Mercury Magnetics site you will find a large selection of iron to fit just about every need (www.MercuryMagnetics.com).

Sergio and Paul both told us there were very significant differences in iron on the same models of amps from the same era. Sergio spoke of a conversation he’d had with Leo Fender about amp components. Leo told him the Fender Company experienced a swelling of demand for amps when young people became enamored of guitar. Fender was just trying to meet the enormous demand so they put out specs for things like power transformers to various suppliers. The suppliers had a lot of latitude in how they meet the specs, creating a lot of variation in the parts.

Here’s another new bit of tube amp knowledge I learned from Sergio. He told me all magnetics (iron) in an amp need to be broken in over a 20 to 40 hour period of playing time. He said initially, there’s a slight harshness in the tone, which can also be characterized as a lack of sweetness. The magnetics have to be thermally and magnetically cycled. Apparently, it is similar to breaking in a speaker. Paul later told us he’s had guitar players call him up after a month to describe the new subtleties and complexities emerging from the amp: a wonderful and unexpected surprise.

After spending about 45 minutes on the phone with Mikey and me, Sergio turned us back over to Paul. I must say it was a pleasure and an honor to speak with Sergio and he couldn’t have been more gracious in taking his time to explain all of the information I’ve relayed above.

Paul and Mikey made arrangements to take the exact measurements of the bolt placement and chassis openings in the DRRI for a new power transformer. I sat back for a bit as Paul and Mikey continued where they’d left off the night before, talking about new amp ideas Mikey has been considering, which will involve creating an amp using a wide variety of power tube options. It’s too early to go into details about that though. I’ll have to save that for another article :>)

By the way, we got to know a bit more about Paul Patronete. He is a key associate of Sergio who talks with guitar players and amp builders all the time, helping people decide which Mercury Magnetics iron is right for them. You can tell he really gets off on helping players attain tonal nirvana.

Of interest, before coming to Mercury MagneticsPaul was the General Manager for Groove Tubes for many years. I dug out my copy of Aspen Pittman’s “The Tube Amp Book – 4th Edition” and sure enough, there is a picture of Paul on the inside of the back cover. He’s also listed in the very front of the book in the “Strokes for My Folks” page and a color photograph of his Orange amps is also in the book.

Well, I’ve gone through all of my notes from my discussions with PaulSergio and Mikey so I guess it is time to close this chapter. I’ll be picking up my amp tomorrow although it will have the stock DRRI power transformer in it until a new one is manufactured. I sure am glad Paul took the time to talk to me, educate me, and with Sergio’s help, convince me to get a Mercury Magnetics power transformer to go along with the rest of the Mercury iron in my amp. I’ll make another trip to Mikey’s shop in Baltimore next month and I’ll be sure to let you know how it sounds, so stay tuned.

Source: https://mercurymagnetics.com/pages/news/misc/WayneReno.htm

3rd Power Amplification American Dream 1×12 Combo Amp Review

3rd Power Amplification may be a fairly new name in the amp business, but don’t mistake that for inexperience. Designer Jamie Scott has chased perfect tone for several decades, a quest that began in his early days as the original (and current) guitarist for the San Francisco metal band, Vain. Debuting at the 2010 summer NAMM show in Nashville, the handwired, Fender Deluxe-inspired American Dream is the second amp to be released from 3rd Power.

American Built, American Vibe
The American Dream is a 1×12 combo utilizing a Celestion Alnico Gold speaker housed in a very striking and unique cabinet. The cab incorporates 3rd Power’s triangular speaker chamber, which is designed to eliminate standing waves and enhance clarity. There are two vents that let sound escape through the sides of the amp, as well as a removable triangular back panel that lends a touch of open-back sound. With its white Tolex and salt-and-pepper grille cloth, the American Dream looks very mid-century American. And adorned with a black control panel with white

The front panel is fairly sparse, given there are two channels available. From left to right, Channel 1 (the “brownface” channel) features an input, Bright switch, Volume, and Tone controls. Channel 2 (“blackface”) also has an input and Bright switch, but is followed by Volume, Treble, and Bass controls. A global Presence knob and 3-way switch with settings for 22 watts, standby, and 10 watts is adjacent to the Power switch and jewel light. The back panel has an IEC power input, fuses, and four speaker outputs (16Ω external, 8Ω internal, and 8Ω internal + 8Ω external).

The American Dream runs on a pair of 6L6 power tubes and boasts a two-stage preamp that uses 12AX7 preamp tubes. Staying true to the vintage concept, there is no effects loop or reverb on the amp.

Plug and Play
Because it’s not bogged down by bells and whistles, getting a good tone with the American Dream pretty much comes down to plugging in and playing. You’d have to work hard to get a bad sound out of the amp, but make no mistake — that doesn’t mean there isn’t a lot of tonal variety inside. Plugging my Les Paul into the Brownface channel, I dialed in a killer, dirty tone that conjured up sounds reminiscent of the first Montrose record. There was some of the low-end splatter that comes from a cranked Fender, but that’s part of the charm of playing this style of amp. Note definition and clarity was superb and dynamic response was excellent. This is a very touch-sensitive amp. Without accessing the guitar’s volume knob, I went from clean to dirty just by digging in harder with the pick — and this amp likes hard picking!

Like many vintage brownface amps, there is less headroom and the mids bark a little more. But the triangular internal design and side vents open up the sound and give it a wide, dimensional quality that feels like full-blooming stereo compared to the highly focused and compressed projection of a normal, closed-back cab. Removing the triangular back panel lets the amp breathe even more, and the tone opens up accordingly. Engaging the Bright switch adds more top-end spank and chime, while the Tone control, though somewhat subtle, offers plenty of range.

As I explored this channel, I found the global Presence control becomes more effective as the amp revs up in volume. This control is voiced in such a way that the tone never gets harsh or brittle, just fuller and more cutting in the mids.

Clear as Black
Moving to the Blackface channel gave me more headroom and clarity, making the American Dream perfect for mating with pedals. The combo revealed the full character of just about every pedal I threw in front of it. If you’re a guitarist who favors pedal textures, this amp makes a perfect blank slate.

Switching guitars to a Fender Stratocaster made it clear why the combination of Strat and Deluxe has always been so revered. From the first chord, the American Dream was bold, chimey, clear, and powerful. The response of the amp felt like an extension of my nervous system. It was both immediate and springy, giving me the feeling of the guitar being played back from the amp. Typically when I play with this clean of a setting, my amp feels a little too unforgiving, but in this case it was positively inspiring. At full volume, the American Dream gave way to a beautiful, blooming gain that was warm, detailed, and willing to get rude with a little force from my right hand.

When I switched to the 10-watt output setting, I experienced an apparent, but not huge volume drop. The most obvious change was in the response. It became a little darker in tone, but there was also a spongier feel and faster breakup in the tone. I liked this setting for pushing the amp and getting some grit without killing everyone in the house with volume, and I could see the effectiveness of this option for clubs. It’s a great feature and adds useful tonal variety to what seems like a very simple amp, when you look at the front panel.

The Verdict
The American Dream reminds you how much you can do with simplicity, and how a few knobs can offer a wide world of tone. The innovative cabinet design opens up a new dimension in sound dispersion, and the amp makes you never want to quit playing. For all its clarity and richness, it makes pedals sound terrific. And while it isn’t a small combo, it doesn’t weigh a ton. It’s easy to see myself taking the American Dream along with a few pedals to just about any gig and getting every tone under the sun. One can dream, right?

Buy if…
you love classic American tones and want a perfect blank slate for exploring pedal tones.
Skip if…
you need a Swiss-Army amp to feel like you’re getting your money’s worth.
Rating…

Source: https://mercurymagnetics.com/pages/news/PremierGuitar/PremierG-27.htm

An Excellent Choice Transformer

We always maintain a steady flow of gear arriving for review, but sometimes we also employ a fascinating if time-consuming research strategy that involves logging onto eBay, picking a broad category such as “guitar amplifiers,” and settling in for as long as it takes to patiently scroll through every page of listings. Yeah, that’s often 50 pages or more, but since we can’t possibly think of all the items that might interest us and search for them by name, it’s far more revealing and productive to just hunker down and scroll. Rarely do we fail to find something intriguing that would have otherwise been missed, and such was the case on a morning in August when we stumbled on a listing for a 1959 tweed Deluxe. Were we looking for a tweed Deluxe? Nope. Wouldn’t have crossed our mind at the time…. We had already reviewed 5E3 reproductions from Fender, Clark and Louis Electric within the past 3 years, and we have frequently referenced our 1958 Tremolux as being our desert island #1. Isn’t a Tremolux just a tweed Deluxe with tremolo in a bigger box? No… not even close. That would be like saying you wanted to date a blonde – any blonde. For the record, our fixed bias Tremolux possesses a cleaner tone with a bigger, booming voice created by the taller Pro cabinet. The Two Fifty Nine is a completely different animal….

Sporting a February 1959 date code on the tube chart, the ’59 had been listed by a seller in Arkansas who turned out to be Tut Campbell, formerly a well-known guitar dealer in Atlanta. Still buying and selling gear, Campbell had described the Deluxe as being in original condition with the exception of a replace output transformer – a big old mono block Stancor dating to 1957. Given the otherwise original condition of the Deluxe, which included the Jensen P12R, we made Campbell a “best off” below his asking price and scored the amp for $1,850 shipped. We wouldn’t say we stole the Deluxe, but it seemed a fair price of admission for the opportunity to experience and explore still another rare classic and supremely worthy piece of Fender history on your behalf.

The Deluxe arrived with the big Stancor dangling from the chassis despite Campbell’s careful packaging. Wasn’t his fault, really – in a feeble effort to avoid any additional holes being drilled in the chassis, the fellow who installed the Stancor in the ’60s had merely tightened set screws over the small tabs at the base of the heavy tranny, which was designed to be mounted upright – not hanging upside down in a guitar amplifier. Of more concern was the fact that while the amp was lighting up, there was no sound…. Well, we’ve been here before, so we made a call to God’s Country and the Columbus, Indiana domicile of Terry Dobbs – Mr. Valco to you. We had already set aside a spare output transformer (Lenco, McHenry, IL) that had been the original replacement installed in our ’58 Tremolux when we first received it, replaced with a Mercury Magneticsfor our June ’07 review article. Mr. Valco cheerfully answered his phone and as we explained the situation with the Deluxe he agreed to walk us through the installation of the new replacement – a simple process involving four lead wires being connected to the rectifier and output tube sockets, and the speaker jack. As long as you put the correct wires in the right place, a piece of cake, and we had the new tranny in within 10 minutes. Pilot lamp and all tubes glowing, still no sound…. Valco patiently guided us through a series of diagnostics with the multi-meter and the Deluxe was running on all cylinders, pumping 380 volts. Stumped, and with the hour growing late, we called it a day. Leaving the mysteriously neutered Deluxe chassis on the bench until tomorrow.

Morning came with a whining voice delivering a plaintive wake up call – “It’s got to be something stupid and simple….” Inspired by a huge steaming mug of Jamaican High Mountain meth, we sat back down at the bench, tilted the innards of the Deluxe chassis forward beneath a bright halogen desk lamp and peered in for answers. We began slowly examining the chassis in sections, looking for broken or dull solder joints, loose or broken wires, while gently pushing and prodding wires and connections with the eraser tip of a #2 pencil as we had seen Jeff Bakos do so often at his bench. After ten minutes or so we were about to give up, when we turned our attention to several places where the circuit was grounded to the chassis adjacent to the volume and tone pots, and damned if a solder joint for one of the uninsulated ground wires hadn’t separated from the chassis. No ground, no sound, and as soon as we had restored the solder joint the Two Fifty Nine arose from the dead with a mighty A major roar.

The amp was indeed remarkably well-preserved in all respects, with the typical amber patina of old tweed. The burnished chrome control panel remained bright and clean with no corrosion, the original handle remained intact, and a couple of small ciggie burns on the edge of the cabinet added a stamp of historic legitimacy to the Deluxe’s pedigree. The top half of the Jensen’s frame was coated in a fine film of red clay dust from the Delta, and while the cone was in remarkably good shape with no tears, an audible voice coil rub called for a recone. We would send the speaker to Tom Colvin’s Speaker Workshop in Ft. Wayne, Indiana, requesting that he leave the original unbroken solder joints for the speaker wires intact if possible.

Meanwhile the first order of business was to listen to an assortment of NOS tubes from our stash, and audition no less than a half dozen speakers. Different sets of power tubes and individual preamp tubes will sound surprisingly different, so we started out with a matched pair of NOS RCA 6V6s, a GE 5Y3 rectifier, and an RCA 12AX7 and 12AY7. From there we subbed in a dozen different RCA, Amperex, Tesla and GE 12AX7s, noting varying levels of brightness, warmth and intensity among them all. For an edgier, more aggressive voice, the GEs and Amperex typically deliver the goods, while RCAs produce a slightly warmer, richer, fuller tone. We also experimented with a 12AT7 and 12AX7 in place of the lower gain 12AY7, and while those tubes ramp up gain and distortion faster and with more intensity than the 12AY7, they seemed like overkill for us. Our Deluxe possesses a tone of gain using the stock 12AY7.

Rather than repeatedly reloading the Deluxe with different speakers, we used a Bob Burt 1×12 cabinet built from 100-year-old pine for our speaker tests. The original Jensen had never been pulled from our amp, but multiple speaker replacements in an old Fender inevitably cause the speaker mounting screws to loosen in the baffleboard, making speaker swaps unnecessarily clumsy and complicated. When we do run into loose mounting screws, we simply run a few small drops of Super Glue around the base of the screw and surrounding wood. Allow to dry and your screws will stay put provided that you don’t torque the nuts on the mounting screws like an idiot with a socket wrench. Don’t be that guy,

We tested a range of speakers that included a Celestion G12H 70thAnniversary, Colvin-reconed ’64 Jensen C12N, Eminence Wizard, Private Jack, Alnico Red Fang, Teas Heat, Screaming Eagle, Red, White & Blues, and Warehouse Green Beret, Veteran 30, Alnico Blackhawk and Alnico Black & Blue. The Alnico speakers generally produce a tighter, smoother, slightly more compressed tone, with a variable emphasis on upper mid-range and treble frequencies, while the speakers with ceramic magnets possess a wider, more open sound. Higher power ratings of 75W-100W offered by the Red, White & Blues, Screaming Eagle and Warehouse Blackhawk typically translate into more graceful handling of bass frequencies, and in a 20 watt Deluxe, zero speaker distortion, for a clean, powerful voice.

Let’s cut to the chase with speaker evaluations, shall we? It has become clear to us that even after reviewing a dozen speakers in as much detail as mere words allow in a single article, many of you remain uncertain about which speaker to choose. No kidding. We would absolutely love to hand you a single magic bullet when it comes to speaker swaps, but here’s the dirty little secret about choosing speakers…. The overall character of the amp you will be installing your new speaker in is critical, and to some extent, the type of guitars and pickups you play most often are important, too. Tailoring your sound with the unique gear you play is not a one-size fits-all proposition – you have to invest some thought into the process. Are you going for a classic “scooped” American Fendery tone, or something more British, with a bit of an aggressive edge and upper midrange voice? Are you playing guitars with single coil pickups or humbuckers? Is there a specific, signature tone you are searching for, or are you playing a wide variety of musical styles that requires a broader range of tones? Do you like the more open sound of speakers with ceramic magnets, or the smoother compression of Alnico? What are you not hearing from your amp and the speaker that’s in it now? Do you want a brighter tone, darker, better bass response, or fuller, more prominent mids? Do you want to really drive the speaker and hear it contributing to the overdriven sound of your amp, or do you want a big, clean tone with no speaker distortion in the mix? The truth is, if you don’t know what you want, you are far less likely to get it. On the other hand, nothing is accomplished with paralysis by analysis. To be perfectly honest, there are lots of speakers made by Celestion, Eminence, Warehouse and, if you can wait long enough for them to break in, Jensen, that we could and would be perfectly happy with, but we would also choose them carefully, taking into account all the factors mentioned above. After a couple of days spent swapping speakers, we ultimately concluded that we preferred the ’64 C12N for a classic tweed Deluxe tone, and a broken-in Celestion G12H 70th Anniversary for the most mind-altering 18 watt Marshall tone we have ever heard. Seriously. More on that in a minute….

Having split more than a few hairs with our speaker swaps, it was time to start picking nits off of gnats with some output transformer evaluations. We first contacted Dave Allen of Allen Amplification, who also stocks Heyboer transformers built to his specs. We found a variety of appropriate output transformers on Allen’s site that offered subtle variations on a stock original Deluxe OT, and we asked Dave to describe the TO26 model we wished to try in the Deluxe:

“The TO26 was intended as a hot rodding upgrade to a stock Deluxe Reverb OT. While maintaining the stock 3-1/8” mounting centers, its fat stack of hotter core steel and multi-tap secondary make it a good choice for builders wanting to maximize the performance of a pair of 6V6s and who may also want to push the envelope with 6L6/5881s while still being able to clear the speaker in a stock cabinet. There are physical limitations in small amps, so its short low profile is welcome. The orientation of the laminations is also good for low hum pick up from the power transformer. I found that an OT mounted the tall way (like my TO30D) picks up considerably more hum simply due to its orientation to the power transformer, so, shoe-horning a ‘tallish’ OT into your amp may cause it to pick up hum from the power transformer – not much of an upgrade. “The TO26’s 7K to 8 or 16 ohm rating makes it ideal for a pair of 6V6s as well as 3,500 ohm to 4 or 8 rating for 6L6/5881s. Notice you always have an 8 ohm option with both types of power tubes. An impedance switch could be wired (I use a blackface grounding switch) as a power tube type selector for an 8 ohm speaker to go between 6V6s and 6L6s. The TO26 will typically give slightly more output with 6V6s due to its more efficient low-loss core steel and will keep the bass clean longer for more perceived clean headroom. As it takes the most watts to reproduce the bass, you notice distortion there first, and since Fender-type amps are so bass heavy, you can quickly hit the wall with headroom, so a noticeable increase in clean bass response certainly feels like a more powerful amp with the TO26. It is kind of like you installed a new speaker with a larger ceramic magnet that is more efficient than the old speaker. The amp is a little louder and the bass a little tighter or cleaner.

“There seem to be a lot of 6L6-based 5E3 amps out there now to get a little clean headroom from a circuit normally not known for much of that. The TO26 is a good choice for that type of amp as it will fit typical available chassis and cabinets. It has extra long 12” topcoat leads ready to strip and solder. I would reckon it would handle up to about 30 watts before starting to saturate and compress – plenty of cathode-biased 6L6s. I find that the Heyboer paper stick-wound and interleaved output transformers with premium core steel and heavy core stacks have typically better clarity or definition than ‘stock’ OTs. Call it fidelity or whatever you want – just clearer distorted and complex tones and better separation of notes in chords, etc. I use the TO26 in the Allen Sweet Spot, Accomplice Jr. and Hot Fudge with Nuts amps with excellent results. All of these amps can use either 6V6 or 6L6 power tubes. You know how a 5F6-A or Super Reverb has that huge 4 bolt OT for a pair of 6L6s to get the maximum clean bottom end? That is sort of what the TO26’s OT is to a pair of 6V6s. It just doesn’t even come close to saturating.

When we informed Dave that we planned to run the Deluxe with 6L6/5881 power tubes as well as 6V6s, he recommended that we try the TO26 since it had been specifically designed for such applications. He also sent a smaller TO20 transformer, described as being designed with a wider 1-1/4′′ lamination “fat stack” that provides 60% additional core mass than typical ¾′′ stack units for improved performance. The TO20 is a direct replacement for Blues Jr. and Princeton Reverb amps, and also suitable for dual EL-84 amps with an 8 ohm load.

Mr. Valco also sent us a replacement 5E3 output transformer he had bought on sale from Clark Amplification a few years ago made for Mike Clark by Magnetics Components in Schiller Park, IL – a company that has been producing transformers since 1943, having been the primary supplier for Valco and various Gibson amps in the ’50s and ’60s. A call to the company revealed that ToneQuest ReportV12. N1. Nov. 20104the transformer Valco sent was essentially their replacement for a Deluxe Reverb, model #40-18002 without bell ends per Clark’s request. We also learned that the company offers a complete range of Classic Tone vintage power and output transformers, including a reverse-engineered clone of a ’55 Triad 5E3 output tranny, model #18022.

We also contacted Paul Patronete at Mercury and requested a ToneClone “brown Deluxe” output transformer, since Larry Cragg had provided them with specific measurements from original OT in Neil’s ’61 tweed Deluxe, confirming that it was indeed a ’61–’62 brown Deluxe tranny. With a total of 6 output transformers to listen to, we took the Deluxe to Jeff Bakos, who set up a rig on his bench that enabled us to clip in each transformer and very quickly switch back and forth between them as we played a guitar through the amp. Are we having fun yet? Here’s what we heard:

Lenco – An excellent authentic “vintage” vibe for those that prefer the classic, if somewhat murkier sound of a tweed amp being pushed, lots of sag in the low end and a jangly pop in the top. And “old,” rather “lo-fi” sound indicative of the ’50s era amps.

Magnetics Components Clark Deluxe 18002 – Similar to the Lenco, but stronger and more robust, with a prominent growling character and voice. Thick, wooly and willin’ with better treble presence and clear string definition then the Lenco, yet an entirely “vintage” character. This tranny is comparable to those found in Deluxe amps from the brown era through silverface. Excellent power, punchy and fat with exceptional clarity and tone.

Magnetic Components 5E3 Clone – Percussive and dynamic with a faster attack response than the Clark/Deluxe Reverb version, this transformer was reverse-engineered from an original ’55 Deluxe OT. IT imparts an intense, throaty tweed character with enhanced mid and treble presence, remarkable clarity, and an authentic vintage ’50s vocal tone with softer bass response and slightly less volume and power than the Deluxe 18002.

Allen/Heyboer TO20 – An interesting variation with a much more modern, percussive dynamic character. The sound was not as heavy and imposing in the vintage style, and with this transformer the Deluxe reminded us of the more refined sound of a Fender Princeton, with excellent dynamic punch for slide and Allen/Heyboer TO26 – As advertised, the low end held up loud and proud with very little sag and an audibly higher threshold of clean headroom, although beyond 6 on the volume control the Deluxe was still holding nothing back. Overall, this transformer imparts a cleaner, high fidelity tone with more clarity and stout bass response than a typical stock 5E3 transformer. An excellent choice for enhanced low-end and maximum volume.

Mercury Magnetics brown Deluxe – Immediately recognizable, the Mercury displayed a trademark sound that is smooth, exceptionally musical, warm and balanced. Sounding more “high fidelity” than the Lemco or Magnetic Components transformers, but still seductively unruly enough to get yer ya-ya’s out. Sweet, rich, detailed and sticky.

Now, you may be wondering why we would bother to audition so many output transformers…. How much difference can it make? Well, forty-odd years ago when someone rigged that old Stancor tranny in the Deluxe, the only choice available to most repair shops was whatever was on hand in the scrap pile. Today we can shape the tone and dynamic response of an amp with a variety of “vintage” or more modern, custom transformers that allow us to recapture the original sound and feel of the amp, or improve upon the original design. Why did Cesar Diaz install output transformers for a Twin Reverb in Stevie’s Super Reverb amps, and Bassman transformers in his Vibroverbs? Because the first thing that chokes and overwhelms a smaller output transformer are the bass frequencies, and Cesar wanted Stevie’s amps to produce a rock-solid, thundering low end that could handle his massive wound strings. The tone we’re celebrating with our ’59 Deluxe is quite the opposite…. The raucous sound of the amp teetering on the edge is the key to it’s exploding tone, but if you wanted to go in the opposite direction with more headroom and a tighter low end, transformers like the TO26 have been specifically designed for that purpose. We once replaced the output transformer in our Pro reverb with a bigger MercuryToneClone Bassman, and the Pro grained a tone of clean headroom and unyielding bottom. Wanna make it even harder still? Use a plug-in diode rectifier in place of the 5AR4 rectifier tube. No saggy britches now. As with so many choices we make in the Quest for tone, the final decision comes down to your mission and individual taste, and Jeff agreed that between the Heyboer TO26, both Magnetic Components trannies and the Mercury brown Deluxe, the question wasn’t which one was “best” – all four were exceptional, but different. Some players would prefer one over another for different reasons described here, but all of them represent stellar examples of just how far we’ve come since the day that old Stancor tranny was used to put the Two Fifty Nine back into service.

One last detail needed to be addressed…. Could we safely run the Deluxe with 5881s or 6L6s if we preferred that sound over 6V6s? Once again, we asked the prescient Mr. Valco for some Hoosier insight:

“The impedance mismatch in this particular amp using the 6L6s is really not a big concern, it won’t hurt the amp and will either sound good or it won’t. The 6L6s draw 1.8 amps and two 6V6s draw 0.9 amp, so using the 6L6s will add about 1 amp more current draw that the power transformer needs to supply from the 6.3 volt heater windings. On some small 6V6 amps, using 6L6s can and does cause the power transformer to run hotter because more current equates to more heat. The concern is that the power transformer in the Deluxe, not being a large one to start with, has the extra 1 amp of heater current capacity to safely use the 6L6s. One way to determine if the power transformer is really stressed out with the 6L6s is to measure the AC heater voltage on pins 2 and 7 on the power tube sockets (or on the pilot lamp) and see if the AC voltage drops significantly from the reading using 6V6s versus 6L6s. It should be a bit over 6.3 volts AC with the 6V6 anyway (since the wall voltage is higher these days than in the early ’60s) and with the 6L6s you sure don’t want to see a large drop in voltage below 6.3 volts AC. If there is a large drop it means the transformer is having trouble supplying enough current for the 6L6 heaters if given enough time with the 6L6s could damage the power transformer. If the drop is only a few 10th of a volt, and doesn’t go below 6.3 AC, then it would indicate that the transformer is supplying the demand for the heater current and should be OK. Most Fender amps used power transformers that could handle some extra current demand.

And now we arrive at the moment of truth. We’ve been steadily reeling in a parade of new and classic amps for review in these pages for 12 years now this month – Marshall, Fender, Magnatone, Hiwatt, Vox, Valco, Silvertone, Ampeg, Gibson, Gretsch, Mesa Boogie, Park, Supro, Dickerson, Traynor, Budda, Western Auto, Standel, Dumble, Cornell, Clark, Crate, Divided by 132, Reeves, Bad Cat, Gabriel, Fuchs, Koch, Star, Category 5, 65 Amps, Balls, Bakos, Callaham, Blankenship, Reinhardt, Grammatico, Siegmund, Chicago Blues Box, Roccaforte, Headstrong, Rivera, Mad Professor, Talos, Maven Peal, Reverend, BC Audio, Savage, Goodsell, Fargen, Carol-Ann, DST, Two Rock, Germino, Matchless, Louis Electric, Swart, Demeter, Juke, Aiken, Bluetron, DeArmond, Carr, Victoria, and Dr. Z, with more coming. Lots of amplifiers, multiple models from the same builders, and among the foremost classics – Fender, Marshall, Vox, Hiwatt, Gibson, Ampeg and the entire Valco catalog, we have acquired, optimized and restored dozens of amps considered to be among the most desirable vintage models ever built. In the 20 watt wheelhouse occupied by the Two Fifty Nine, it has no equal by a mile. Game over.

After a lot of back and forth testing with different sets of output tubes, we became hooked on the thundering sound produced by a pair of Philips small-bottle 6L6WGBs. Thanks to Larry Pogreba’s talent for scavenging rare tubes (in Montana, no less), we are flush with several outstanding and stout pairs of RCA 6L6s, but the brighter Philips really lit up the Deluxe with a fresh and lively attitude that mirrors the bounce of a newer amp. With the ’64 Jensen C12N loaded, the Deluxe spookily nails the tones of Neil Young’s rig on Ragged Glory – a “studio” recording cut live with the Deluxe and Old Black in a barn on Young’s ranch with Crazy Horse. With the volume backed off to 4-5 a bluesy jangle emerges anchored by solid low end, rich midrange, the sweetest treble tones imaginable, and variable levels of sustain and edgy distortion that can be controlled both by the volume on the guitar and pick attack. The Deluxe does not discriminate between single coils or humbuckers, ravaging both with equal fervor, and the responsive dynamic character of this amp simply is not of this world. Rotating the single tone control sharpens treble without dumping lows or mids, while also subtlety increasing gain, as if you were using a boost pedal. A “Y” cord plugged into the Instrument and Microphone inputs enables the two channels to be mixed with great effect. As Neil Young described, bringing the mic input volume up with the instrument volume set between 6-8 gradually deepens the tone while slowly igniting an intense explosion of thicker second order harmonics and distortion as the dynamic character of the amp softens. Pushing the Instrument volume level up into the 8-12 range brings the volume up to a perceived level that exceeds 20 watts, while provoking an angry, pissed-off cascade of astonishingly rich musical distortion as the notes swerve into controlled harmonic feedback.

Switching from the Jensen to the Celestion transforms the Deluxe into the most stunningly toneful 20 watt Marshall you could possibly imagine. To be honest, you probably can’t imagine it, because we have never heard anything like this ourselves, even after owning a couple of vintage Marshall PA20s, a rare Lead & Bass head and 1×12 cabinet, and a Balls 2×12 18 watt. We could easily live with either speaker, and the Deluxe also just kills pushing our 8 ohm 4×12 pinstripe cabinet.

For those of you who appreciate a somewhat tamer vibe, we can assure you that the Deluxe loaded with a fine pair of 6V6s is equally mind-altering. The overall sound is a wee bit smaller in girth and less imposing, yet abundantly overflowing with vivid harmonic depth, a supremely touch-sensitive response, and brilliant combination of fidelity, clarity and bloom. Compared to a black or silverface Deluxe Reverb, the ’59 presents a more musically complex soundstage, less harsh, stiff and linear, and it lacks both the sharper treble of a blackface amp, and the scooped midrange character. The tone is rounder and meatier, the treble sweeter and less dominant, with an enhanced 3-D image.

Now, if you’re the type that skeptically requires a qualifier to add a stamp of legitimacy to such an over-the-top review, here it is, Mr. Been There-Done That…. The Deluxe doesn’t and won’t spew big clean tones at stage volume. Our ’58 Tremolux produces a cleaner tone with a higher threshold of clean headroom by far at comparable volume levels, and the taller tweed cabinet encourages a stronger, cleaner resonant bass and low mid response. The Tremolux is also equipped with a Mercury ToneClone Tremolux output transformer, which creates a tone that is less wooly, raucous and indistinct.

The busted-up sound of the Tremolux above 5–6 is gloriously righteous indeed, but with more clarity and less provocative intensity than the Deluxe. Taken in context, what we’re suggesting here is that in our experience, the Deluxe has no equal as both a Fender and Marshall style 20 watt rocker (depending on speaker selection), and we’ll add “blues” to that description equipped with 6V6s and the Jensen C12N. During our 2-month test period, we also routinely used our Lee Jackson Mr. Springgy reverb, Analogman-modded Boss DD3 digital delay, and a very cool, versatile (and cheap) Flip tube tremolo pedal reviewed here. Can a modern replica of the 5E3 Deluxe deliver the same inspiring tones as the Two Fifty Nine? The closest thing we’ve heard is the Louis Electric “Buster,” but no, magical happy accidents like this Deluxe can’t be reproduced today – and that is as it should and shall always be. Quest forth…

 

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Custom-Wound Mercury Magnetics Transformers

Like the pedal business, the number of amplifiers being built by smaller builders has mushroomed into a garage and basement Skunkworks industry that is constantly changing. New guys pop to the surface and ride the momentum created by chat rooms and social media, while others quietly slip beneath the surface in an unfortunate imitation of Beach Boys drummer Dennis Wilson, never to be heard from again. The desire amongst certain guitarists and collectors to own the latest, supposedly greatest new amplifier is a power drug, and for some, a hard habit to kick. We enjoy discovering small batch alternatives to familiar archetypes and affordable production amps, too, but since we’re doing so on your behalf, our initial evaluation process lacks the unbridled enthusiasm of a new owner who has already made the plunge financially and emotionally. Still, when a giddy reader calls or writes asking us to review their new killer amp, we routinely hit the builder’s website, send an introductory email and wait for a response. Such was the case with the Tungsten Cremawheat and builder Adam Palow

Ultimately, the Cremawheat turned out to be another exceptional amplifier as our review reflects, but as is so often the case, the story behind the name on the face plate is as interesting as the amp. Listen….

TQR: You mention on your website that you were inspired and intrigued many years ago by your first tube amp. Do you recall what it was?

It was a 1965 Fender Vibro-Champ that was missing the face plate, and the grill cloth had been replaced with a red and black check material that looked like it had been on a sofa. I think I was around 16 when I got it, and no matter what I played through it, the amp sounded very musical compared to the solid state practice amps had used before. It was the beginning of an obsession. I started chasing down vintage Fender amps wherever I could, and I met a guy who showed me how to safely drain the stored voltage in an amp, how to use a soldering iron, and he explained how bigger caps produced more low end. From that point forward I was on my own, and everything I have done since has been the result of trail and error and experimentation. I’m limited in some areas because I don’t necessarily understand all the theory, but in another sense it’s empowering because I am chasing feel and working in an intuitive way rather than strictly by the “book.” My favorite part of the build is constructing the board and wiring the chassis. If there is any artistic expression in building an amplifier it’s in the way the board is constructed. Of course, in the larger picture, it’s completely meaningless.

TQR: What were the most significant things you learned through hands-on experience working with guitar amps, and the five years you spent working on Hammond organs with Bob Schleicher?

The thing that blew my mind the most once I had acquired multiple identical models of the same amplifier like the Fender Blackface Bassman and Bandmaster was how different they could sound from each other even though they were built with the same components. That also carried over into my work with Hammond organs, because every large Hammond console also had its individual voice, and I attribute that to the accepted variance in parts values, and individual and very unpredictable drift in these values over time. You also see random parts stacking where some of the capacitors may have been oriented the correct way and others not. When all the caps are pointing the right way you can have an amp that sounds faster, and when they are oriented the wrong way the amp can sound slower. On the old caps there was usually a band marking the outer foil, and whether or not they were oriented correctly often just seems like chance. Some companies paid strict attention to that and others did not. Even if I am building ten identical amplifiers in my own line, there are going to be variances between them – not only in the tolerance stacking, but in the way the tubes bias to the cathode resistor. I have an absolute minimum standard – it has to inspire me or I’m not going to ship it out, but every once in a while you drop in the right rectifier and the right power tubes and they just match up perfectly with the cathode resistor and it makes your hair stand up on end. Magical. Yet that same amplifier with a different set of tubes may not do the same thing.The Hammond organs are unique because not only do they have an extremely rich and harmonically complex signal, but they have infinite sustain with no transient attack unless you’re using the percussion feature, so when you’re dealing with Leslie power amplifiers you’re not dealing with sag. You’ve got compression going on because you’re driving it with a very wide band signal, but because there is no transient, you’re not experiencing sag, compression and release in that order. I spent a lot of time rebuilding Leslie amplifiers, and there was a very specific type of distortion coming from those 6550 Tung-Sols – a low, grinding, wooly distortion kind of like the Marshall of the organ world in a lot of ways, and I caught that sound in my head. It was very musical, and it had a lot of clean qualities, but also an outrageous amount of overdrive on tap, and even when it was driving hard there was still enough clarity to retain a musical quality in the distortion. You could really hear the notes and the intervals between them, and that’s the complaint I had with a lot of amplifiers outside the vintage world…. They swung so far into breakup and distortion that you lost the clarity of the notes. There was more noise than tone, and the place I’m coming from is a more musical place. The other aspect of my work with Hammonds is that I gained a huge amount of experience with vintage Jensen Alnico speakers.

TQR: We have always wondered if the Jensen speakers used in Hammond cabinets were similar to those made for guitar.

In the Leslie, the Alnico P15LL and later C15NLL bass driver that shoots down into the rotating horn were definitely not guitar speakers by any stretch. The 12 inch Jensens I’ve seen bear all the same markings as standard Jensens for guitar, the differences being that they have black frames with no Jensen sticker, and the Hammond code starting with the letters “AO” have been silk-screened on the frame. I have pulled P12Ns out of old Hammond A100s, as well as P12Qs, and if they were specifically designed for organ, they are also the best sounding guitar speakers I have ever heard, and I have used them to base my own speakers on made by Weber.

TQR: Which prompted the development of your own line of proprietary speakers?

Yes, and I didn’t really have to start from the ground up because they had already come close to the mark, but I wasn’t hearing the same extended frequency response that I was hearing from the vintage speakers, and it was just a matter of developing a different recipe. Fortunately, when Ted was still alive we went through the process of mixing and matching components, just trying to get that sound. I didn’t care if the parts were period-correct – I just wanted them to sound right. I tried to do the same thing with the ceramic line, but we just never nailed it and I never put them into production. Of course, the goal in developing the Alnico speakers was to produce the low-wattage, medium fidelity, $6 replacement speakers that they were originally.

TQR: Looking at the different models you build today, it’s obvious you prefer the sound of tweed-era amplifiers.

Yes, I cut my teeth on blackface amps, but when I built my first tweed Champ I became one of those guys that ditched my pedalboard and plugged straight in. For me it’s all about that very alive midrange, and the dynamic response you get out of the power section. I was instantly hooked. I also have a fondness for the lower power brown amps as well, but when it comes to what I personally want to plug in to and play, I really need to feel the response of a tweed power section.

TQR: What’s your approach to specific types of capacitors used in building your amps?

You have to let your ears be the guide, and everyone hears things differently. Every quality capacitor has its place, but I personally prefer the sound of Mallory 150s in tweed amps. Other people feel that they are too bright in the upper mids until they break in. I tend to break in my amplifiers for 72 hours and when I take breaks from building I’ll plug into every amp that’s burning in. The truth is, everything matters. In the Cremawheat, for example, there different capacitors are used in the tone circuit to color the tone in a certain way. It’s one recipe. I also use custom-wound Mercury Magnetics transformers in everything. Some of them are custom-wound because I wanted a different gauge of wire, and others because I wanted a different secondary voltage. When we’re talking about power transformers, voltage that you’re sending out to the circuit makes much more difference than the brand you’re using. With output transformers it becomes more critical. Some people want to hear a darker transformer, others high-end clarity…. Some people want a smaller core so it saturates sooner, and others want enough iron so that it never saturates. All of those factors play not only into the sound, but they hugely affect feel.

TQR: Can you briefly summarize each model you build?

The 8 inch version of the Mosaic comes with either the stock 5F1 (Champ) output transformer or the oversize version, which nets you perhaps an additional 2 watts. You get more punch rather than volume. I also build a 12 inch Mosaic Mark II with an additional tone knob, which gives you more bass.

The Cortez was intended to be my flagship model until the Cremawheat came out. The name was inspired by Neil Young’s Suma album – you can just hear the tweed all over it. Its 12W-15W with 6V6s and it bumps up to about 18W with 5881s or 6L6s. It’s basically a straight-ahead 5E3 design.

The Cremawheat is my attempt to retain the tone and feel of a great 5E3 Deluxe, while giving you the dynamic range that would otherwise be lost in the output transformer and speaker with that amp. Those were two choke points on the 5E3, and the third being the massive amount of bass that’s being sent through the circuit, which causes it to distort so early. The other significant feature in this amp is the British-voiced Scumback speaker. It adds punch to the dynamic range, and enough bass, but not the ragged and loose 5E3 style low end.

The T35 covers the 5F4, 5E5-A and 5E7 circuits for the Bandmaster, Pro and Super. They were basically the same chassis with a couple of minor resistor changes and three different speaker configurations, and I tend to prefer the 1×15 and 3×10 versions. It’s the only fixed bias amp I offer. I like the T35 series, but I tend to gravitate toward the cathode biased amps and most of my customers seem to as well.

If you took the 2-input ’55 Bassman, which shares a lot with the Super, Bandmaster and Pro amps of that era, and cathode biased it in a 2×12 speaker format, that’s kind of where the Blue Point sits. When you pay it clean, it sounds very American in the style of a mid-’50s Bassman, and as you turn it up, you get more coloration from the British-voiced speakers. It starts to cross the Atlantic into that early JTM-45 Bluesbreaker tone, but stops short of a later Plexi amp.

The Buckwheat is the follow up to the Cremawheat. It’s a 6L6-based, 30 watt with the Scumback H-75, which is their version of the pre-Rola G12H. It has a significant amount of headroom over the Cremawheat, and the speaker produces a glassier, high-headroom tone with a bigger transformer and a larger cabinet that leaves more air around the notes. If you’re a Telecaster player, for example, who wants more headroom with just a little hair, this is that amp.

TQR: Will you build specific amps with different speaker configurations as a head or combo, and what is the current lead time for an amp?

Sure, I’ll absolutely build variations on the stock models – I actually really like the 16 inch Mosaic and I have built several of them. I want to know that I’m building exactly what a customer wants. The lead time right now is eight weeks, and I always try to keep it under three months. I sell direct, and through a small dealer network, but I do enjoy working directly with customers. Depending on what a customer wants, I may suggest a specific change to the stock circuit, and I find that interaction very rewarding Introducing another 15W–20W amp in these pages is nothing new – in the past year we’ve invested a log of ink highlighting amps like Jeff Beck’s choice of a Pro Junior, our vintage ’59 Deluxe and ’76 Princeton Reverb, the Retro-King 18W and the Trace-Elliot Velocette. Why? Because we understand that such friendly decibel levels offer adequate volume for use in small clubs, mic’ed on bigger stages, yet till fill your house, studio or practice room with a mighty roar when needed. Small amps just make more sense today for most players, but like us, you might be wondering just how many ways a smallish guitar amplifier can be designed and built to produce a genuinely unique voice and vibe. You know what you’ve already got, but what might you be missing, and at what point does your quest to discover the ultimate low power amp become redundant, at best? A fair question, and given the nearly infinite variables created by the marriage of different components within different circuit designs, we are happy to report that we haven’t reached the end of the road in the quest for tone quite yet.

Viewed within the board context of the booteek amp landscape, the Tungsten Cremawheat emerges from the box as an uncommonly attractive natural blonde. Offset with gold grill cloth, it scores big in style points without even being lit up. Nor will you find any self-conscious bells and whistles added to an otherwise classic design, as if the builder wanted to get noticed by adding the kind of stuff we seldom really use – like Selmer-style rotary tone switches, pentode/triode modes and toggled boost switches (although Carr has always done those right by bypassing the tone stack). Indeed, this amp is so outwardly attractive, approachable and comely that pulling the back panel off might inspire distant memories of an anticipation experienced in concert with a one-handed thumb and forefinger bra removal technique. (We now pause to allow a moment of fond reflection. Please take your time.) Adam Palow’s skill in assembling and soldering up a circuit board culminates in nothing less than a work of art. Flip the chassis over and the custom-wound Mercury Magnetics trannies provide further evidence of Palow’s commitment to following his muse. In practical terms, you get four inputs into two channels (bright and normal), volume/volume and tone, plus a standby switch and extension speaker jack.

Our first session with the Cremawheat was agreeable enough, but repeat visits left us with a nagging impression that something was either missing, or perhaps technically present, but not being fully reflected in the sound of the amp. Naturally, we used our tweed Tremolux and Deluxe for benchmarks, and the Tungsten sounded subdued and restrained by comparison. We tried different tubes first with no appreciable change, and that’s when we focused our attention on the Scumback speaker. Admittedly, we had suspected it from the beginning, so with the original tubes back in the amp, we connected the Celestion G12H30 70th Anniversary in our ’59 Deluxe cabinet to the Cremawheat, fired it up, hit a big E chord raking a heavy Pyramid pick over the strings slowly, followed by ten minutes of unbridled delirium. Paired with the Celestion, the Tungsten bowed up with increased volume, clarity, dynamic punch, and a gloriously rich tone that easily rivals that of our Deluxe, but with a little more added sparkle. Swapping the stock Electro-Harmonix 6V6s for a pair of RCA 6L6s brought the Cremawheat to climax with an even bigger, more imposing voice, precisely in the style of our ’59. If anything, the Tungsten offered a slightly more defined and chiseled tone as a new amp should when compared to one that has undergone a half century break-in period.

To be fair, we called Adam Palow to inform him that while we absolutely loved the Cremawheat, we were not feeling the Scumback. He agreeably acknowledged that the Scumback was indeed somewhat more subtlety endowed than the Celestion, which is why he offered the G12H as an alternative for players desiring maximum girth, power and growl. Any number of modern speakers would surely sound outstanding in the Cremawheat – but we clearly preferred the more vivid soundstage created by the Celestion when the choice is narrowed to one of the two stock speakers offered. Would we buy and play the Cremawheat? Absolutely. It now reigns among the best on temporary boutique twenty watters, and in four important respects (tone, overall clarity, availability and price), the Tungsten impressed us as an irresistible alternative to a vintage Deluxe and any and all modern replicas

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Low-wattage Combo Amps a Boon for Any Guitarist

The en vogue status of low-wattage combo amps remains a boon for any guitarist on the lookout for a compact amp. Just about every major amp company and most boutique shops are offering at least one model in the 12- to 18-watt range and that’s a great thing. What’s not to like about an amp that you can push hard without blowing out the windows or that you can throw in the front seat of your car for a gig?

Nolatone Ampworks — and the work of Paul Sanders — are already standouts in this fast-growing amp category. Hand built by Paul in Raleigh, North Carolina, using only the highest quality parts, Nolatone models like the June Bug and Chimey Limey have already made a mark for their interpretations of Fender Tweed and Vox tones. They might also be some of the sharpest looking amplifiers available today. And on both the sound and visual front, Nolatone’s 15-watt Rotten Johnny is every bit as spectacular a performer as its cousins in the Nolatone line.

The Dirt
Weighing in at a very reasonable 28 pounds with dimensions similar to a Fender Blues Junior (18″ x 16″ x 10.5″), the Rotten Johnny is an open-back 1×12 combo constructed of solid dovetail-jointed pine. Our review Rotten Johnny came in covered in two-tone brown and crème vinyl with basket weave grille cloth, and sported the signature Nolatone “V” panel TV front design. The 12″ speaker is a 25-watt Warehouse Green Beret, which is designed to sound like a broken-in Celestion greenback. The circuit is built around two JJ 6V6 power tubes (you can also request EL84s) and two 12AX7s. Everything under the hood is top-notch, including custom Mercury Magnetics iron, 1-watt carbon film resistors, F&T filter caps, Switchcraft jacks, and Carling switches laid out on a hand-wired turret board.

Unlike many lower-wattage amps, the Rotten Johnny offers far more control options than a single volume and tone control. The top panel consists of a unique 3-band EQ (Bottom, Mid, Top), as well as Pre- and Post-Gain controls and a Master volume. A Mid Lift switch (which can also be activated by a footswitch) effectively works as a boost for solos. Power and standby switches reside next to a red jewel power indicator.

The EQ section is a little more flexible than what you’ll find on a production-line low-watt amp. The Bottom control is a 6-way switch that progressively rolls off bass. The independent Mid control is not part of a typical tone stack configuration — dialing it down extends the highs and lows to create a very Fender-like mid-scooped tone. The High control, meanwhile, is a Vox-style top-boost reverse-wired to enable players to move from chiming to much darker tones by backing off the control. Borrowing a move from Nolatone’s June Bug design, the Pre- and Post-Gain controls work in tandem to control the amount of gain to the second stage and phase inverter respectively.

Rockin’ the Filament
With a Godin Icon Type 2 with Duncan P-Rails in hand, I got right down to the business of exploring the wide-open voice of the Rotten Johnny. With the Godin set to the humbucker position, I cranked the Master to full, set the Post Gain to around noon and brought up the Pre Gain until I got a rich, full distortion. The sound was raw and thick, but I wanted a little more clarity, so I dialed back the Bottom knob by a few clicks, scaling down the thickness a touch, but opening up the sound considerably. The combination was reminiscent of Frampton’s Rockin’ the Fillmore-era Humble Pie tone — a pretty huge sound for a 15-watt 1×12 combo. And if I closed my eyes, I’d swear I was listening to a full stack in miniature. For years, I’ve tried to harness 100- and 50-watt amps with attenuators and master volumes and never been totally successful. Needless to say, I was stunned when two 6V6s pushing a single 12″ gave me what I’ve been looking for—and then some.

Wielding my ’74 Les Paul Custom and with the Mid control set to the non-lift position, I was able to dial in AC/DC rhythm tones with just the right amount of kerrang and chime to create the illusion of a blaring baby JTM45. And setting the Pre Gain to noon and ramping up the Post Gain added gobs of thick, juicy crunch with just enough bark to cut through a mix. This is where the Top control really shines — pulling the Top back just a touch takes some of the edge off without muddying the tone. It’s voiced for just the right amount of sheen and clarity without ever being brittle or ice-picky. The top-cut configuration also makes the effectiveness of the Mid control’s sweep range very apparent — enabling boosts in presence that aren’t too brittle.

The Mid control is almost like another gain knob, delivering more distortion and dimension the more you crank it. And with the Mid Lift engaged Rotten Johnny turns into a roaring fire-breather with more gain than most of us would ever need. I’ve rarely heard a 6V6 amp sound this way — often assuming some of the tonal qualities of EL34s and EL84s. Though it only takes cutting the Mid and backing off the Pre Gain to get back to more blackface-like territory that was a perfect match for my Strat.

For a 15-watt amp, the Rotten Johnny doesn’t lack headroom. Because there is so much control via Pre and Post gain over how hard you hit the tubes, I found myself digging deep into the wealth of Strat-friendly clean sounds you can get with less aggressive use of those controls. It was easy to conjure thick and chewy cleans with just a hint of grind by pushing the Post Gain and leaving the Master wide open. Even with the Mid Lift engaged I could still hit the guitar hard without harsh sounding breakup. And I was always able to shape the thickness with the Bottom switch, which I used extensively to match individual guitars to the amp.

The Verdict

It’s been a long time since I’ve been so excited about a new amp. The Rotten Johnny has a huge range of brilliant tones in a compact design that, at $1399, doesn’t break the bank. For bedroom or studio musicians, it’s a dream because you can coax out cranked stack sounds without knocking down walls and get the most beautiful cleans with the twist of a few knobs. The construction is top notch and the styling is classy and cool. For an amp that’s roughly the same size as a 1×12 cab and weighs less than 30 pounds, it has the sonic personality of something much larger. I only wish this little guy was around when I first started playing guitar. Thankfully, I’ll have the chance to make up for lost time — my own Rotten Johnny is on the way and I can’t wait to cut loose.

Buy if…
you want everything from Brit aggressiveness to blackface tones in a compact package at a fair price.
Skip if…
you actually need the power to blow down barns.
Rating…

Source: https://mercurymagnetics.com/pages/news/PremierGuitar/PremierG-30.htm

Weider Signature Amp

We asked Benjamin Fargen and Mike Piera to comment separately on the development of the Weider Signature amp. Our review follows their interviews…

TQR: Briefly describe the process that was involved dialing in the tone of the amp—how you achieved the higher threshold of clean headroom and power in Channel One, and the Distortion Channel.

Fargen: I built the original JW-40 prototype amp for Jim in late 2004 and it was tweaked over the course of two years as Jim played shows to support his album Percolator. I flew back to New York three times during the process for lone three day weekends of tone tweaking, listening and catching Jim at some live performances. Our job was to outperform Jim’s favorite, modified blackface Deluxe Reverb, which had been his main amp for many years—not an easy task since the amp has some very special qualities that were essential to capture while retaining Jim’s signature sound. We also matched it up to many other vintage Fenders and other high end amps that were in the same league, and when we finally surpassed all of them in tone and clean sustain, we knew we had a good design.

The original prototype amp had less headroom, so we decided to go with a slightly higher B+ voltage to squeeze at ad more headroom out of the amp for larger rooms and outdoor shows. We sorted through many different power transformers, output transformers and chokes from Mercury Magnetics before we found the correct match, and the feel and sound we were looking for.

TQR: The reverb seems to “sit” very nicely in the mix—not too splashy or pingy, and it doesn’t add any unwanted overtones. Did you do anything unusual in designing it?

Fargen: It’s similar to a classic Fender-style reverb with some tweaks to the overall EQ and the amount of return level reverb. I feel that the stock Fender design places too many mid and low mid frequencies in the mix,and I prefer more of a high end sparkle for the reverb to stand out. But the biggest problem with a stock Fender-style reverb is the way it can sometimes walk all over the note rather than work with it. The overall amount of reverb you allow to return to the recovery circuit is very critical to obtain a great sound.

TQR: Describe the Slope feature.

Fargen: The slope feature changes the overall frequency response of the EQ circuit to achieve greater flexibility when matching up different guitars and pickups with the JW-40. Jim and I felt it was nice to have other tonal options that changed the overall wide or narrow” character of the EQ structure. This came in really handy when switching between single coils and humbucking pickups.

TQR: Can you briefly summarize the effect the O-rings on the power tubes seem to have on the sound of the amp?

Fargen: The power/preamp tube dampening rings not only help to suppress micro-phonics and tube rattle, but they seem to produce a tighter sound with a very extended low end range. I find they are very useful for thickening up your amp tone at lower volumes, but some players may want to remove them for higher volume levels since the low end can become excessive with darker guitars or humbuckers.

TQR: What have you learned from the experienced designing, tweaking and dialing in this amp?

Fargen: Working on the JW-40project with Jim has been a great experience—he’s a great player with an amazing ear for tone. We worked very hard to achieve an amplifier design that not only exceeded Jim’s needs and expectations from a signature amp, but would be well receive by other players. We set out to deliver a classic guitar amplifier that offers a tone and feel that extends beyond even the best vintage examples that can be found, so this project really forced me to think outside of the box and develop many new techniques rather than just deliver one of my stock amplifiers to Jim with his name on it. It takes partnerships like this to shakeup your normal routine so that you can push the envelope and continue to grow as a designer/builder. Because, as we all know—if you feel you have nothing left to learn, you should just quit now.

It was clear the moment we played the first notes through the Fargen JW-40 that someone with an extraordinary ear and deep experience had influenced the way this amp is voiced. The Rhythm channel pours out more clean, Fendery headroom than one of our favorite, more powerful blackface amps—the Pro Reverb—an the clean tones are richer,fuller, more detailed, lively and deeper. With the Slope switch engaged in the Rhythm channel, the tone becomes even thicker in the upper mids, creating more of an EQ bump rather than a “boost” that ignites some kind of overdrive feature. We did notice some boominess in the low frequencies using a 4×12 cabinet loaded with Celestion’s Gold Alnico G12sand G12H30s, and in our Balls2x12 cabinet with an oval “football” open back design and British optimally voiced for an open back cabinet. There may also be some bias on our part at work here, because we have never cared much for the sound of a Fender amp with a closed back cabinet.

As noted in our discussion with Ben Fargen, the reverb in the JW-40is unique in the way it remains in the back-ground, enhancing, but not overwhelming or washing over the notes. This is undoubtedly the best reverb sound in a combo amp we have ever heard for an under-stated effect, and even players that normally don’t use reverb may find it difficult to resist.

The Lead channel controls function much like an over-drive pedal, with Drive, Level and Tone controls and a toggled Boost switch. A Midrange control is also included. You couldn’t ask for a clearer, more intelligently designed control panel, and the controls themselves are simple and intuitive. As with many overdrive or boost pedals, mixing variable settings for Drive and Level produce a wide range of intensity, from a fat clean boost to rippin’ overdrive, but unlike a typical pedal, higher Level settings do not push the volume of the amp up to extremes as the Level is increased. In practical terms, this means that you can switch between the Rhythm and Lead channels without having to make dramatic adjustments to the volume on your guitar. We also dis-covered some incredibly tasty overdriven tones at very low volumes with the Level down and the Drive up—kind of like a’50s Gibson GA20 with more fidelity and no noise, and that’s a trick you can’t pull off with many distortion pedals.The Tone control helps shape and color the distortion EQ to suit different guitars and moods, and it can also be used to subtly focus on specific harmonic overtones. But the most remarkable feature of the boost circuit is the “clean”character of the over driven tone. Mike Piera’s mention of David Gilmore is instructive in this regard. Gilmore’s fat, overdriven guitar tones on his solos are indicative of the rich fidelity produced by the JW-40. Chords are clear with distinct note separation, sustain and decay are natural rather than sounding forced or artificially contrived,and the overall sound is round, rich and warm with a sweet, clear top end.Our best description of the over driven voice of the Fargen is “majestic,”and who can’t live with that?

 

 

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VVT Amps Lindy Fralin Model

It only stands to reason that a guy whose day gig involves running his own successful and renowned pickup company knows killer tone when he hears it. So when the Jones hit to seek out a custom made map that combined the best of his favorite Blackface Vibroverb and Vibrolux, Lindy Franlin called upon Tony Albany and the guys at Vintage Vacuum Tube Amps to see if they might be up to the task. And that they were.

The holy grail would be to produce a 6L6 based 30 watt tone machine capable of a beautiful clean sound as well as a smooth, crunchy overdrive and be put captive into the smallest and lightest workable cabinet.

Beginning with a 2×10 Mojotone Tweed Super amp kit for the basic prototype, VVT and Fralin tweaked their hearts out for six months until they got it right.

Residing in a rather compact 20×20 cabinet, the VVT Lindy Fralin Model strikes a vintage pose in its white Tolex with oxblood-like grill cloth.

Beginning with a 2×10 Mojo tone Tweed Super amp kit for the basic prototype, VVT and Fralin tweaked their hearts out for six months until they got it right. Residing in a rather compact 20×20 cabinet, the VVT Lindy Fralin Model strikes a vintage pose in its white Tolex with oxblood-like grill cloth.

The VVT Lindy Fralin Model is a cathode biased straight forward, no bells and whistles affair. The “Plexi”top panel is simple and clean with its Input, bright switch, volume, treble and bass controls followed by the reverb control, standby and on/off switch. Chicken-headknobs let you know where you’re at. Two TAD matched 6L6 tubes supply the power with two 12AX7s for the preamp. A pair of 12AT7s are for the reverb driver and phase inverter. Rectifyin’ is courtesy of an Electro Harmonix 5U4GE. The cool thing is that the Lindy Fralin Model can also accept a deuce of 6V6s in place of the big bottles in the power section for a whole different vibe. Because of the higher plate voltages, VVT Amps stresses that only modern tubes (like the supplied JJ Electronics) should be used. You don’t want to blow the thing up, do ya?

If you think a 15 inch speaker might get as loose and floppy as your Auntie Mabel’s arse, you might be in fora pleasant surprise. With an obviously wider bass frequency range than a 12 inch, the Weber’sbottom remains tight and punchy with a nice lower mid section as well.Single coil and humbucker equipped instruments alike snuggled up quite admirably to the Weber Classic.

First impressions? The Lindy Fralin Model with my Strat spoke with gorgeous single coil chime and harmon-ic complexity, unabashedly magnified with a full trans-parent tone and organic beefy sustain. Very articulate and touch sensitive, the amp displays a more than impressive amount of projection. Both Lindy and Tony attribute this to the cross shaped members (called an integral diffuser) placed across the speaker opening in the baffle board which help disperse the sound and tame some of the“beamy” high end.

All tone controls are unobtrusive and very musical. While the treble is subtle up to around 6 on the dial, the bass is more evident from the get go but remains trans-parent throughout its range with no muddiness. The bright switch surrounds the notes and chards alike with an airiness without compromising the inherent full tone of the amp.

In addition to the Strat, the Lindy Fralin Model warmed up nicely to my other 6 string friends. The Carvin California Carved Top sounded sweet and detailed while my Ibanez AS200spoke with a very articulate, full and warm bodied tone.

Arch tops? This little box makes a nice jazz amp as well with clear, well defined chord structures and beefy single notes. With the fat axes pushing the volume past 3-1/2 caused a little mush in the low end which could probably be remedied by changing the first preamp tube to something with a bit less gain.

The reverb fills out the sound with a pleasant mix behind the dry signal. Throughout its range, the effect is very complimentary and doesn’t send your playing out to see even when dimed. For the dirty stuff, cranking the chicken head to the red(!) produced a bubbly, organic and throaty overdrive with real honest to goodness preamp/amp interaction. Very sweet with gobs of sustain. Doing a quick swap to the matched pair of 6V6s morphed the amp into a kind of Blackface Deluxe vibe with breakup noticeable at lower levels. The bottom felt a little less tight with a bit more perceived glassiness in the top end.

Whereas the 6L6 bottles speak “tux and bow tie” the6V6s are more “t-shirt and jeans”—not quite as complex but with a grittier and nice fat tone.

Also VVT Amps’ attention to detail gets a big thumbs up for the extra long line cord and groovy little spare fuse holder inside the back of the amp.

The collaboration between VVT Amps and Lindy Fralin has turned out to be a winning combination. The VVT Lindy Fralin Model’s beautiful, three-dimensional tones are equaled only by its straight-forward and no-nonsense design.

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Transformers 101

Hey, you guitar players… don’t think for a minute that you should skip the following articles because they are too technical. You’ve dropped some big money over the years on your guitars and amps, right? Transformers are the very heart of every amplifier, and your output transformer can influence your tone every bit as much as your choice of pickups, tubes, and speakers. Our attention was recently focused on output transformers after one of our all-time favorite “keeper” amps, a blackface Fender Pro Reverb with an amazing pair of Jensen Vibranto speakers went down with a bad output transformer. (By the way, Pro Reverbs remain some of the best vintage bargain tone machines every made, and why they have failed to receive the high praise and prices reserved for blackface Super and Deluxe Reverb amps is mystifying. Get yours now.) Cesar Diaz kindly sent us a new Mojo Tone replacement OT, and it was immediately apparent to us that although we had always considered the tone of our Pro to be extraordinarily good, things had improved significantly after installing the new OT. The amp had more punch and power with less sag, and that got us wondering if output transformers could slowly decay over time, subtly sapping the full potential of a great amp. We concluded that it can, which led us to consult with a couple of experts on the topic of guitar amplifiers and transformers. We asked Victoria Amplifier founder Mark Baier (aka Sam Bisbee) to comment on his experiences with OTs, along with the premier builder of custom amplifier transformers on the planet, Sergio Hamernik of Mercury Magnetics. Sergio has been blueprinting exceptional vintage examples of the great transformers of the past and supplying discerning guitarists and their technicians with accurate reproductions that succeed in delivering authentic vintage tone. Stay tuned for reviews.

TQR: Good morning Mr. Bisbee. Your mission, should you choose to accept it….

Yikes, I expected the computer to go up in a puff a smoke!

So you want to know the inner secrets of output transformers, eh? Be forewarned – once you make that commitment, you’ll be cursing the days when you slept through “Advanced Frightening Mathematics 300….” How’s this for a wake up call? The following is the very first paragraph from Chapter V of the venerable RCA Radiotron Designer’s Handbook (4th ed.).

TRANSFORMERS & IRON CORE INDUCTORS

(i) Definitions

An ideal transformer is a transformer in which the winding reactances are infinite, and in which winding resistances, core loss, leakage inductances and winding capacitances are all zero. In such a transformer the voltage ratio between any two windings is equal to the turns ratio of the windings under all conditions of loading. Also, in such a transformer the currents in any two windings are inversely proportional to the ratio of turns in the windings under all load conditions….

The entire chapter is 53 pages long!

To keep things from getting out of hand, let’s just say that there are many factors influencing output transformer performance. Aside from an obvious fault like a shorted winding, fatigue of the core (the metal laminations) is the most prominent consideration in transformer output and tonality.

Fatigue is a natural consequence of normal operation. Suffice it to say that it’s a veritable Fourth of July inside the atomic workings of your output transformer every time you bust your best licks through it. The magnetic properties of the metal used in the core, the type of laminate used, the size of the core, and many other factors contribute to the final performance and longevity of the output tranny. Actually, most guitar amplifier transformers are made of rather inexpensive materials (yeah, try telling that to your parts supplier). The real high end stuff ends up in mega bucks hi-fi and industrial applications. In the grand scheme, guitar amps don’t rate the kind of respect we tone geeks assign to them.

To understand why a tranny gets fatigued, let’s remember what’s happening in the OT. You are transforming a high voltage/low current signal into a low voltage/high current signal. There are lots of electrons jumping around from point “A” to point “B.” This creates magnetic relationships and phenomena that act to age (or fatigue) the characteristics of the iron. Over time, the constant forces acting on the core change the ability of the laminate material to perform its duty efficiently. It will saturate quicker, and it reacts differently than when it was new, thereby altering the tone and performance of the amp.

To be sure, this is a slow, incremental change, and one which will take years of use to manifest as a perceivable degradation in tone. In fact, one of the reasons we like old ’50s amps is the quicker saturation and compression of an old, fatigued tranny, so don’t get too spun out of shape thinking your tone is being sucked away by a tired transformer. It may be your personal ticket to tonal nirvana. Just remember, however, that old amps with old trannys means old everything else, too… yin and yang.

Most of us are looking for the most reactive, intuitive amp that our minds and fingers can handle. In many cases, if the amp is checking out A-OK but it’s otherwise sounding a bit soft and saggy, perhaps a popping a new transformer in is just the ticket. Replacing an output transformer is not an inexpensive procedure, but it’s a simple one, and one that is easily switched back if the results are less than fruitful. As to the question of swapping out old components like caps and resistors that test and sound good, I advise leaving the old ones in when we are dealing with vintage pieces, the qualifier being that these components should test and sound good. Unless the ’57 Bassman amp in question is going to be used on an extended 300 date tour to sold out sheds, leave it alone. Most vintage amps will let you know that they’re giving it up by an audible degradation in tone and performance. Let’s face it, a 40-year-old capacitor will most likely fail in the next couple of decades (especially filter caps), so consideration must be given to the intended application of the amp. For most weekend warriors, the original passive components will suite you fine if they test and sound good. One last thought on the use of increasingly expensive NOS tubes in an amp that is old…. You will have to determine if you want to jeopardize a $259 pair Mullard EL34s in a vintage 40-year-old amplifier. When a coupling cap decides to fail, it can put the tube in a potentially dangerous operating point, causing it to fail too. I know I’m kinda swinging both ways here, but in this case, the vintage geek wins out (let’s not forget the tales of unscrupulous techs carving all the old Astrons out of vintage amps and then turning around and selling them for big bucks – it does happen, folks).

I could go into a more, more, extra more technical explanation of what’s happening in an OT, but I don’t want to lose everybody in a run down of big math with variables like reactance, gilberts, and flux densities that would scare everybody into suicidal seclusion….

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FBFDR-P-E

Blackface Reverb — Universal Voltage Primary

FBFDR-C

Blackface Reverb and Brown Deluxe — #125C3A  — 2″ Mounting Centers

FBFRT

Brown, Blackface & Silverface Spring Reverb Transformer — #022921

FDR-OM

Blackface Era OT — 4 & 8 Ohm Secondary — 3-1/8″ Mounting Centers

FDR-O

Blackface Era OT — Single 8 Ohm Secondary — #125A1A (#022640)

Same size as original OT with 3-1/8″ Mounting Centers

FDR-OX

Blackface Era OT — 4, 8 and 16 Ohm Secondary — 3-1/8″ Mounting Centers

FBFDR-OM

Blackface Reverb Era — 2, 4 & 8Ω taps — 3-1/8″ Mounting Centers

FBFDR-O

Blackface Reverb Era — Single 8 Ohm Secondary

Larger than stock #125A1A — 3-9/16″ Mounting Centers

FBFDR-PM

Blackface Reverb — lower B+ — 315-0-315 VAC

FBFDR-PMM

Blackface Reverb — lower B+ — 290-0-290 VAC

FBFDLR-P

Blackface — #125P23C — 1 1/2″ stack — Low Flux Density version of FBFDR-P

*Same 350-0-350 VAC as FBFDR-P

FBFDR-P

Blackface Reverb — #125P23C — 1 1/2″ stack — 350-0-350 VAC

FBFDR-P-EL

Blackface Reverb — Universal Voltage Primary — Lower B+ — 340-0-340 unloaded

FBFDR-P-230M

Blackface Reverb — 230V single primary

FDRP-20

Blackface Reverb — 1 3/4″ stack — #025130

FBFDLR-P-E

Blackface — Universal Voltage Primary — #125P23CX

FDP-20-240M

Blackface Reverb — 270-0-270 — 53V bias winding. 120V & 240V primary

FDP-20-U

Blackface Reverb — Universal Voltage Primary

FBFDR-P-FS

Blackface Reverb — #125P23B — Upgrade! — 2 1/8″ stack

FDP-20

Blackface Reverb — #125P23B — 2 1/8″ stack

FDP-20-100-120

Blackface Reverb — 100V & 120V primary

FDP-20M

Blackface Reverb — lower B+

FDP-20M-E

Blackface Reverb — lower B+ — Universal Voltage Primary

FDP-20X

Blackface Reverb — FatStack — higher B+ — great for use with two 6L6 / KT66 / EL34 type tubes

FDP-20X-E

Blackface Reverb — FatStack — higher B+ — great for use with two 6L6 / KT66 / EL34 type tubes — Universal Voltage Primary

FDR-OX-M6

Blackface Era OT — 4, 8 and 16 Ohm Secondary — Uses grain oriented iron

Benefit of Using Mercury Magnetics Transformers

OK, so perhaps you’re sold on snatching a stock Pro Junior, but of course, you want it to sound the best it possibly can…. Should you wish to dig a little deeper in the quest for tone, veteran amp builder Ben Fargen has developed a line of Hot Mods for stock production amplifiers – lots of them, including the Pro Junior, and we asked him to describe the inspirational behind his concept for the Hot Mods….

“For a number of years I had a lot of people wanting me to work on their vintage Fender, Marshall and Vox amps, and I really never had the time until the economy slowed down in 2008. A local customer asked me to take a look at a Marshall JCM800, which (laughing) really isn’t the kind of amp I’d usually be interested in, but I agreed to look at it, got in touch with Mercury Magnetics, went through the schematic, and wound up turning it into a really great sounding high-gain amp that would appeal to people who like that sound. I had also done some design work for Carvin when they wanted to optimize a production design and get the most out of it, so when the economy slowed down I began taking in specific camps to upgrade, and from there we started developing mod kits. Customers went just their chassis in, which isn’t expensive to ship; we do the work and ship it back.

Through the later part of last year we were doing about one mod project a day, at first taking in just about anything, but we’ve since whittled it down to specific amps like the Pro Junior, Blues Junior, Blues Deville and the reissue blackface Deluxe Reverb, for example. With these amps it’s not the design that’s the problem – it’s just that the component selection is based on what is most practical and economical for an affordable production amp. We take those amps and optimize the sound as if production cost was not an issue, and we have customers who have had two or three different amps modded now, because they are basically getting a boutique amp and the tone that comes with it.

TQR: In the Pro Junior specifically, what areas of the circuit do you focus on for the mods?

There are really only so many ways to wire up a tube amp circuit, and in most cases we’re focusing on the same key areas in each amp – plate resistors, coupling caps in the EQ and phase inverter, and slop resistor for the EQ, and cathode resistors and cathode bypass caps are huge and often overlooked…. We hone in on the tone-shaping improvements that give us the biggest bang for the buck, and of course the Mercury transformers make a big impact. You can do any of these mods alone and improve the sound, but it’s really the cumulative benefit of using specific high quality components and the Mercury Magnetics transformers that determine the end result where you really hear the magic. We aren’t the only people doing mod kits, but you’ll notice that we use specific brands and types of caps and resistors in very specific places with our mods, and that’s the result of my having build amps for 12 years and learning what specific types of components are going to do in a particular part of the circuit.

TQR: You also added a power supply choke in the Pro Junior you modded for us….

We add the choke because it is so critical to what I call pick dynamics – the note response to pick attack, and improved sustain. Most budget amps just have a power resistor separating the B+ and the screen voltage – it works and does the job, but the correct choke in a circuit really adds a huge amount of that ying and yang you want to hear between the power amp and the preamp.

TQR: And what is the cost of the Pro Junior mod as you’ve done this amp?

With the full Mercury transformer set it’s $499 without a speaker swap. All the Hot Mods are in the $349 to $549 range until you get into 100 watt or JTM45 Marshall reissues and things like that. We’ve also done a lot of mods for the reissue Bassman…. As you know, there is nothing like a great Bassman, and there are a few revisions that Fender made that are just not happening at all, but when you get rid of those they can sound fantastic.

Here’s the deal…. You economically ship your chassis per Fargen’s instructions and they ship it back fully optimized. We asked Ben to send us a Hot Modded current production Pro Jr. for review and we directly compared it to our stock 2001 Junior, fully loaded with our NOS tubes and Jensen Vibranto. The modded amp Ben sent included stock Groove Tubes and a new Celestion Greenbackten.

As soon as we played through the Hot Modded amp, we heard the same dominate midrange push and lack of treble presence we had heard at first in our own amp. Less pronounced with brighter single coils, yes, but still too middy for our taste, so we subbed in the JensenC10Qfor the Greenback and the angels were singing again – sopranos, altos, tenors, and baritones all present I the choir. In fact, both amps sounded similar with the stock tubes in the Hot Mod Pro and our stock model with the NOS tubes – thick, rich and very smooth with excellent dynamic response and full, clear fidelity. Fargen’s Hot Modded Pro Junior possesses smoother, warmer overall tone while our Pro still sounds brighter and a little glassier overall. We suspect that a bias pot and lower voltages would tame the intensity of the distortion, but the 5751 does a nice job as an easy workaround. Fargen’s amp was also a little quieter at idle than ours, although we hadn’t noticed this until we had a quieter amp for comparison. For more information on all of Fargen’s modifications, check out the Hot Mod pages on the web site.

 

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Output Transformer Changed to a Bassman

Hey, Jeff.

I love your column! I look forward to reading it every month. I have a ’67 blackface Super Reverb that I gig with. Really an awesome-sounding amp!

I just realized that the output transformer has been changed to a Bassman reissue or a Super reissue OT (output transformer). I’m not really big on keeping it original — it doesn’t really matter to me because I will never sell this amp — but like every other tone searcher out there, I want the best possible tone that this amp can achieve. I am curious about changing this out for a higher-quality OT. I heard the Mercury transformers are really good vintage replacements. What kind of differences in sound/tone will I hear by doing this, and is it worth it? Also what kind of tubes do you prefer in these amps? Thanks so much, and keep the awesome columns coming!

Ben

Hi Ben,

Thanks for reading PG, and thanks for writing in. It’s the much-appreciated support of the readers that enables all of us to write for such a cool publication. Now… on to that horrible amp you’re forced to gig with. I kid, of course. The Super Reverb is absolutely one of my favorite amps. The multiple 10″ speaker configuration helps give it a unique voice and sets it apart from most other combos using the ubiquitous 12″ speaker. It’s a shame that the output transformer needed to be replaced, but occasionally these things happen. A reissue Bassman or Super Reverb transformer, since they both have an output impedance of 2 ohms, will certainly get the amp working properly, but yes, you can do better.

Mercury Magnetics offers a couple of different lines, and they are some great-sounding replacement transformers. Their ToneClone series transformers are replicas of the original transformer designs, and the Axiom series takes them to the next level with design modifications for tonal improvement. Which one you choose will depend on whether you desire to have the amp sound as good as a great-sounding Super Reverb can, or to, as Emeril Lagasse says, “Kick it up a notch!” Either way, you should notice tonal improvements. Some may be very noticeable, and some may be subtler. Things like tighter, extended bottom end, smoother top end, more harmonic content and better note definition are all improvements you might expect. These attributes can all be affected by the quality of your output transformer. Whether it’s worth it or not is completely dependent on any cost limitations you put on your search for the ultimate tone.

You also asked about tube preference. This is always very subjective and depends on the type of music you play and your expectations of the amp. In general, my preferred preamp tube for amps that were not designed with heavily overdriven preamp sections is the Sovtek 12AX7LPS. Its large plates seem to make it a very full-range tube, so your guitar or effects will be very full bodied. In amps with major front-end gain, this extended frequency range can become too much of a good thing, but that’s certainly not the case with a Super Reverb like yours.

Also, here’s a little helpful tip to remember: Even new tubes can be microphonic. If you install new tubes in your amp and you experience ringing or feedback when the volume is turned up with nothing plugged in, try swapping the positions of all the tubes of a same spec. (In this case, it would be the 12AX7s. The 12AT7 tubes in Supers are in locations that are generally not too susceptible to microphonics, so they shouldn’t be an issue.) Certain locations in the circuit are more susceptible to microphonic tubes than others, so moving them often clears up the ringing, or at least minimizes it.

Preference for output tubes is much more dependent on the use of the amp and style of music. If you play mostly blues or classic rock, I would recommend going with a smaller-bottle tube that will have a nice, smooth breakup that occurs sooner — making it easier for the output stage of the amp to be pushed into clipping and achieve that glorious nirvana that is output-tube distortion! Recommendations might be the new reissue Tung-Sol 5881 or Groove Tubes GT-5881C. If you’re more into big jazz chords or country twang — or if you get your signature tones from stompboxes and prefer that the amp be as big, loud and proud as it can be — you’ll probably want to go with a larger-bottle tube. This generally yields the fullest, cleanest performance. Recommendations here might be the JJ/Tesla 6L6GC or the Ruby 6L6GCMSTR. Another suggestion here might be the new reissue Tung-Sol 6L6GC-STR. I just installed a quartet in a Twin Reverb and it was surprisingly loud ‘n proud. I hope that helps you on your way to a more super Super.

1977 Guitar Amplifier Review

In this issue we are dealing with a subject on which I have received many inquiries in the past. It is about the selection or matching of tube amps for the best possible Jazz sound. Amplifying acoustic or semi-hollow-body guitars has always been a huge challenge because most jazz guitarists are very demanding in terms of sound and simultaneously fight against unwanted distortion and feedback. In the following article I would like to summarize some tips and tricks that get  great tone and how to avoid distortion.

When I started getting involved with jazz sounds, around 1977, most guitarists in this genre used transistor amplifiers. George Benson played a Polytone, Pat Metheny an acoustic amp with a 4×10” speaker cab and Volker Kriegel and Michael Sagmeister used a Gibson LAB L9 with 15” speakers. Such examples can be found very often from that period. Although all of these guitarists had indeed very good tone, the typical depth and openness of a tube amp sound could not be reached however in its wider spectrum. Still the transistor amps had some advantages over tube amps: They sounded very compact and linear, were less prone to feedback and offered a relatively balanced frequency spectrum and a nice sustain, which was the ideal sound of many jazz guitarists. A Gibson L5 played through a LAB or a Polytone is completely convincing – even today.

One disadvantage that the transistor amps had in particularly was its dynamic behaviour, in their relatively poor response and in their tendency to not let the individual character of a particular guitar fully unfold. You could also say: Transistor amps tend to standardise tone.

I do not wish to start a discussion about tube versus transistor because transistor amplifiers will continue to play a rightful role in jazz. It is more about ways to show how one can get the typical warm jazz tone with a tube amp without all the disadvantages.

Above all I am thinking of the sounds of the early sixties, which were marked by numerous jazz guitarists including: Wes Montgomery, Kenny Burrell, the early George Benson, Herb Ellis, Joe Pass, Barney Kessel, Grant Green and Jim Hall. All of these guitarists were playing tube amps on their early recordings and getting fantastic sounds. Today tube amps are celebrating a renaissance with jazz guitarists.

Let us first take look at the most popular models from the distant past. In the fifties the combos from Fender (Tweed), Gibson, Standel or Flot-A-Tone were especially loved by jazz musicians due to their sound and their small size. These amplifiers were sufficient for jazz guitarists because they were usually accompanying musicians and they performed as a soloist only in rare cases. They often stayed in the background and did not play very loud.

Even back then, most jazz guitars were equipped with a tone control that made it possible to filter out unwanted peaks and thus to form the typical dark jazz sound. But soon the guitar became a solo instrument. Just think of the impressive sound of a cascading Les Paul, who at that time had good reason to play on a solid body. The traditional jazz players remained with their hollow bodies and now had to fight against all the disadvantages of the electrification of their sounds. Recently I read in a retrospective of Wes Montgomery that he alleged that during his entire career he was unhappy with his sound because he simply could not find the perfect amp. One might even go so far and assume that the dark jazz sound is actually created only (and eventually cultivated) because the amount of unpleasant highs tube amplifiers have, are rather imperfect sounding and also quickly led to feedback. Most guitarists wanted more of a linear and natural reproduction of their beautiful instruments that already sounded great acoustically.

Let’s now take a look in the interior of a tube amp and consider certain circuit characteristics which can be modified for a better jazz tone. The objectives of these measures are the reduction of distortion and the high frequencies, improving the mid-range and increasing the linearity of the sound.

First, a list of known suitable amplifiers for conversion to a “jazz box”: Fender Tweed Fender amps from 1956 and Brownface, Blackface and Silverface combos. Examples from this list shall be explored in following issues.

Let’s start with a Tweed Deluxe amp replica from Cream which I have converted for jazz sounds. These amps are known for their distortion when left stock and therefore not ideal for a clear jazz tone. But they are very small and handy and with around 15 watts of power ideal for use in a club. In addition, these amplifiers are connected with a so-called “split-load” phase inverter which is appropriate for our purposes because of its low gain. The only drawback is the two coupled volume pots, which restrict the volume control range on the one hand and deliver too much gain in the preamp. The aim is to reduce the gain in the preamp and increase the output power and stability of the amplifier. Only then we get enough headroom for a clear sound.

Just this once, I should like to “put the cart before the horse” because there are a number of measures to improve the amp without intervention on the circuit.

First, these amplifiers usually have an inefficient speaker. Powerful speakers with a good efficiency rating are especially suitable for jazz sounds. Those who love the Alnico sound can search out an old JBL D-120 and replace the aluminum dust cap with a counterpart out of fabric (available from Weber VST). The speaker can be helped dramatically in the highs and we get a warmer, rounder tone. Excellent was also the old Fane Crescendo Heavy-duty speaker, which is also suitable after the removal of the aluminum dome making a perfectly clear and powerful sound. These speakers were also used by David Gilmour. Another excellent choice is also an Electro-Voice 12L or a Jensen C12K with 100 watts. All these speakers better the sound of the Tweed Deluxe significantly. You only have to watch out for the thin baffle-board because vibration during transport could for example pull heavy speakers from the screw holes.

A further stabilizing method is the conversion of the power tubes to 6L6 or 5881, which I recommended at this point several times. Although the amp has only about one or two watts more output, the increase in headroom is very clear. You get more clean reserves and dynamics. Here I recommend changing the cathode resistor of the amplifier from 250 (typically with 5 watts) to 330 ohms with 10 watts. If you play a jazz guitar with humbuckers, we recommend the low input of the normal channels. Here there are less highs and the output signal of the guitar is more attenuated. It should be noted that the volume pots affect each other on the Tweed Deluxe. By turning the unused channel by not more than 70 percent, the tone is much cleaner, but also quieter.

If you don’t wish to utilize this trick, you can simply remove the cathode of the second stage capacitor (Elko 25mF/25 volts) and reduce the gain of this stage substantially, which in turn increases headroom. The amp will be clearer and somewhat linear, but also a touch softer.

Even more clear sound can be obtained by replacing the output transformer. Something I always do in such tuning. In this case I choose a Mercury Magnetics Tweed Pro Axiom FTPRO-O transformer (available at Tonehenge Amplification) with 8 ohms, which gives much more stability to a small tweed amp.

If you want to use the amp only for jazz, you can also decouple the two volume controls from each other and only one channel and a tone control remain. Now you can adjust the volume much finer and linear. The circuit can be found at www.schematicheaven.com under Fender Deluxe 6G3. Here the channels are completely separate, each with their own volume and tone control. It’s only after the volume knobs on the channels that two 220k ohm mixing resistors are mixed together again.

Since the Tweed Deluxe played with humbuckers has in general somewhat bassy sounds, I also reduce the value of the coupling capacitors from 0.1mF to 0022mF. This makes the sound tighter and more mids. Sprague “Orange Drop” P715-type fit perfectly here.

Finally we get to fine-tuning via preamp tube placement. With a good 12AY7 and a 12AX7 of your choice, you can continue to shape your favourite tone. For those of you who have not had enough, you can play with the value of the capacitor on the tone-pot. The Deluxe was originally installed with a 0005 UF capacitor but also possible are values such as 0.01mF or 0.02mF (as in the 6G3) for a slightly warmer tone. If you want to darken the sound one can bridge one of the anode resistors at the 12AY7 with a 0.003mF capacitor (as in the normal channel of the Brown Vibrolux).

The result is a truly compelling jazz amp for small clubs, feeds back less, offers more clean reserves and could compete with any Polytone but all the benefits of dynamic and harmonically rich tube sound can be enjoyed. Diana Krall’s guitarist Anthony Wilson often used a Tweed Deluxe replica from Clark and his blond Gibson Byrdland in the studio. This sound is very reminiscent of Kenny Burrell and offers a wonderfully unique character. Have fun experimenting!

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Output Transformer Upgrade

I have a cool little 1980s Fender Super Champ. It’s one of the amp models that was designed by Paul Rivera. This little guy puts out about 18 watts through a single 10″ speaker. It also features Reverb and an overdrive mode. This is a great little amp to take to jams or recording sessions. It’s an all tube design and one of the last point to point hand-wired Fender amps. A few shortcomings of this amplifier are:

  1. The footswitch design that engages the overdrive mode sucks… it completely changes the tone of the amp the instant you plug the footswitch in.
  2. The stock 10″ speaker sucks… nothing left to say.
  3. The tiny output transformer holds back this little monsters potential.

Two of the three shortcomings can be fixed pretty easily and for not too much money. The one that cannot be fixed is the footswitch circuit… I’ve tried and it’s just the design… oh well. First thing is to ditch the stock speaker and put in one that’s more efficient with more clarity and better bass response. I chose an Eminence Ragin Cajun and the amp totally came to life. You can do a gig with no problem once you install the Cajun.

If you want to take the amp up another level or two then you have to replace the puny output transformer. I removed the stock unit and replaced it with a Mercury Magnetics FBFDR-O model. This is the clone of the blackface Deluxe Reverb output transformer. It is definitely bigger and if you install in on a slight angle you can catch a mounting screw hole for a terminal strip so you do not have to drill any holes in the chassis.

The result is absolutely astounding!! It has been a long time since I upgraded a transformer in an amp and this swap reminded me how effective upgrading an output transformer can be. The whole amp just opened up and the bottom end got much tighter and defined… almost piano like. The overall volume of the amp increased and the dynamic range was broadened. There was much more harmonic content and overall the amp sounded and felt much more solid. Besides sounding and feeling better this amp was now a lot more gig worthy. A simple transformer swap did all that and only took about an hour from the time I dropped the chassis until I hit the first note. To me that’s a total home run!!

If you have an amp that sounds and feels good but want to take it up a level or two then let me suggest two reasonable upgrades: New speakers and a transformer swap… at least the output transformer. These two upgrades can transform your amp into something magical. Plus it is a lot less expensive than getting a whole new amp, not to mention the time you have to invest trying a bunch of them until you find one that works for you.

I am affiliated with both Eminence and Mercury Magnetics. If you have any questions and are interested in upgrades please email me and I can help make a recommendation or two on speakers and/or transformers. You will be amazed… I am every time!!

Amp Transformers, Output Transformers & Chokes

New Guitar Amp Design

THE CREW AT 65 AMPS HAS A REPUTATION for putting considerable R&D sweat into every new amp design before it leaves the maker’s Los Angeles, California, headquarters. The Lil’ Elvis has, in the broad sense, been in development even longer than most — a stately 48 years or so, if you take into account its roots in an odd little combo owned by Vox collector and author Jim Elyea, one that Vox designer Dick Denney had built as his own personal amp, but which never went into production. Having seriously dug this prototype’s overdriven sound, 65 Amps’ Dan Boul and Peter Stroud set about tidying up the circuit, giving it a usable clean voice and a much broader vocabulary, and making it into a versatile — yet still quite simple — club-gig and studio amp for the contemporary tone fiend. The result is 65’s most diminutive offering yet, both in physical stature and output level, but as we shall see, the stated “clean output” of 12 watts can be deceiving, and this isn’t the mere bedroom brawler that such a rating might imply.

The format hints at a blend of American and British small-amp templates: from this side of the pond, a quirky split-phase inverter similar to that of Fender’s Princeton Reverb and a “bias wiggler” tube tremolo circuit not unlike that used by some Gibson and Ampeg models — from the other side of the pond, the dual EL84 output tube complement and EZ81 tube rectifier. And from California circa 2009, plenty of fresh thinking in the form of the Bump and Master Voltage circuits and the squat, chunky cab, as well as the considerable effort that went into transformer design (with Mercury Magnetics), grounding and filtering topologies, and noise reduction techniques. The Lil’ Elvis is also a somewhat simpler affair than other 65 products, and comes in at a little less coin as a result. Its Bump feature is fixed — rather than having its own Tone and Level controls like the one on the SoHo and Stone Pony — though it is footswitchable (from a pedal that also includes a stomp button for the tremolo), and EQ is limited to a single Tone control. There’s also an enigmatic Smooth switch that has no noticeable affect on clean settings, but does exactly as it says when you crank the amp up, by engaging a circuit that keeps the grid from lifting up from ground when you go into heavy distortion, thereby reducing crossover distortion at the output stage. The final control on the panel, labeled Master, actually governs a proprietary “master-voltage” circuit that lowers the preamp and power tubes’ output levels while retaining filament voltage and, hence, is purported to preserve tonal vocabulary and playing feel.

The stout 21″ wide x 18 high ” x 11.5″ deep cab wears the traditional 65 Amps two-tone cosmetics with aluminum front-edge cooling vents, and houses a single Celestion G12H-30 speaker. Inside, the workmanship lives up to everything I’ve come to expect from this high-end maker, offering a superb example of handcrafted tube amp manufacture. Of the whole package as it sits, my only minor gripe might be that it’s tricky to change the horizontally mounted tubes, requiring a blind grope inside the cab, but it’s easy enough flip the whole chassis outward, panel still attached, to do the job more carefully. Oh, and why “Lil’ Elvis”? In Boule’s own words: “No matter how small you make Elvis, he still rocks.”

I tested the Lil’ Elvis with a Fender Telecaster, a Collings 290 with Lollar P90s, and a Gibson SG with humbuckers. Played clean, it issued classic blackface-Fender-style tones, with piano-like lows and silky highs, with good headroom up to higher Volume settings than I would have expected. Cranked up, this sonic template segues into a surprisingly convincing Marshall half-stack impersonation. There’s a juicy midrange that isn’t over-baked, surprisingly solid low-end thump, and velvety smooth highs that really help your lead playing to soar — especially with the Smooth switch engaged. Stomping on Bump makes everything thicker and bigger, enabling serious rock lead and rhythm work alike from this deceptive little amp. And although it would be nice to be able to set the amount of extra boost that this feature introduces, it’s still a groovy option. The Master control works as it should, retaining body and character as you lower the output level, but it does increase the depth of your given tremolo Intensity setting, an unexpected quirk, but one that’s not too problematic given that you’ll most likely adjust it and leave it — and likewise set Speed and Intensity to taste — before you launch into playing. For its own part, this output-bias modulating tremolo circuit is a real sweetie, adding rich, chewy, chop to your sound and attaining a sense of depth and vibe at higher Intensity settings that must be heard to be appreciated.

Containing a few nods to classic amps of the early ’60s, but tied together with a lot of original design work, Lil’ Elvis is one chunky bundle of surprises. This top-notch tone machine is surprisingly versatile despite its simplicity, and it sounds way bigger and badder than you’d ever imagine 12 watts could provide. So if you’re gunning for a low-power amp that wields some serious mojo, Lil’ Elvis is the ass-kicker you’ve been waiting for.

SPECS:
CONTACT 65 Amps, (818) 760-5089, 65amps.com
MODEL Lil’ Elvis
PRICE $2,150 retail/street price N/A
CHANNELS One
CONTROLS Volume, Tone, Depth, Speed, Master, Smooth switch, Bump switch
POWER 12 watts
TUBES Three 12AX7 preamp tubes, two EL84 output tubes, one EZ81 rectifier
EXTRAS Series effects loop, two-button footswitch jack, dual speaker outs, switch for 8Ω & 16Ω impedance
SPEAKER Celestion G12H-30 (16Ω)
WEIGHT 49 lbs
KUDOS Great build quality. First-class clean and overdrive tones. Surprising versatility.
CONCERNS Tubes are tricky to change without removing chassis; tremolo strength increases as Master Voltage is decreased.

Source: https://mercurymagnetics.com/pages/news/GuitarPlayer/GPDec09.htm

Great Bedroom and Studio Amps

CATEGORY 5’S ANDREWAND Typhoon Joe are all-tube, handwired two-channel amps with top-of-the-line Mercury Magnetics transformers, JJ and Tech-Cap electronics, Analysis Plus speaker wire, and silver-tinned Teflon wire, all attached to a two-millimeter aluminum chassis in an 11-ply Baltic birch cabinet fitted with Jensen Neo speakers.

Both amps have multiple-impedance capability, two speaker jacks, a line-out, and an adjustable line level.

There are controls for two non switchable channels on the front panel, with Volume and Tone controls for the first, and Volume, Treble, Middle, Bass for the second. A section labeled Global affects both channels, with a single control for reverb.

Using a reissue Gibson Les Paul Special with P-90 pickups and a kit guitar with Rio Grande single-coils, the 45-watt Typhoon Joe (with four 12AX7s, two EL34s and a solid state rectifier) sounds great and is a snap to control in terms of volume. Adjusting its overall output via the Wattage control lets the amp maintain its tonal characteristics no matter how many picture frames fall from the walls! There is a slight increase in headroom as voltage is dialed up, and a softening of the edges on the distortion as the voltage goes down, but it’s very subtle. And the EQ is remarkably consistent – a relief for those who’ve played amps that require channel-volume adjustment and tone-knob tweaks if they touch the Master. An A/B comparison confirmed the characteristic was common to both amps.

With its dual EL34s and 100-watt/12” speaker, the Typhoon Joe pushed out gorgeous tones with a distinctly British voice. Channel one gives a straight-up Marshall JTM45-like tone with single-coil pickups that help it produce a combination of mid range throatiness with high-end chime. The Typhoon is relatively clean (for a Marshall-type amp) to just past half-way on the Volume dial. Keep it below that, though, and it’s oh-so-easy to get Robert Cray-style cluck. Channel 2 has a late-’65s Marshall plexi tone at lower volumes, but the distortion become screamier as the Volume knob is dialed up. Even at upper settings, there wasn’t a hint of harshness, just more sustain.The P-90s had Channel 1 singing with the Volume knob halfway up. Using the bridge pickup with the Volume at three-quarters brought out a tight, rich, distortion, while turning down the Tone smoothed out the edge without killing the highs. The neck pickup was warm,even when driven hard, but did not become muddy, revealing the sound Larry McCray described in a recent interview as “woofy.” The P-90s were pure velvet in Channel 2 from about 40percent on up – rich, with just a bit of edge to keep the notes distinct.

Although the Andrew is rated at a few watts less than the Typhoon Joe, its two 100-watt 10” speakers make it seem louder. Its two 5881 tubes give it a more American sound and, if that’s not to your liking, a bias circuit allows the Andrew to run a variety of octal power tubes, including 6V6, 6L6,EL34, KT66, and even KT77 tubes,without re-biasing. Channel one has a pre-blackface Deluxe tone, if only the Deluxe weighed about 400 pounds.Clean(er) Fender tones prevail up to about halfway on the Volume, and after that it has slightly scooped mids with hair. The bridge-pickup tone was remarkably smooth, with no brittle highs. Channel 2 continued the Fender tones and sounded like a Super, but a little cleaner, like it had mated with a Twin. While the neck pickup was glassy, the middle pickup was called into service more than usual, Channel 2 bringing out the usual warmth of a middle Strat pickup, but with more clarity and aggression.

If you like P-90s, plugging into the Andrew is going to have a serious impact on the amount of sleep you get and how often you get out of the house.The neck pickup had a slight glass-on-steel sound like any good Strat pickup, but the Andrew emphasizes it while bolstering the added mids of a P-90. With the Volume at about 60 percent, the slightly under wound neck pickup was warm, full, and just a little edgy. Combining both pickups with the three-way switch in the middle gave a B.B.-type tone, only a little darker and more menacing. The bridge pickup by itself had more snarl and bite than with the Typhoon Joe.

Though neither Category 5 amp offers channel switching, their channels are in phase, so an A/B/Y footswitch allows for days of tonal exploration. And because of the Wattage control, both amps make great bedroom and studio amps that produce full-bodied distortion at low volumes. – Bob Dragich

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Original Power Transformer in our ’73 Super Lead

While Michael Bloomfield was playing cranked up blonde Fender Bassman and blackface Twin Reverb amplifiers, Marshall 100 watt stacks suddently appeared thanks to The Who, Jimi Hendrix, Cream and Led Zepplin. Throughout the ’70s, rock was dominated by the sound of a Les Paul and Marshall amps, but despite its reputation as the ultimate rock machine, all four-input, 100 watt Marshall model “1959” heads are not the same….

The first 100 watt Marshall amps appeared in late 1965,and despite Marshall’s decision to drop tube rectifiers for the less forgiving, harder sound of solid state diode rectification, the “Plexi” 100 watt heads remained more closely related to earlier Marshall amps inspired by the tweed Bassman than the Super Leads that would follow. In the early ’70s, the 50 watt model “1987” head and 100 watt Super Lead were gradually modified to produce more gain faster, and the bright channel was pushed to a punishing level of thin, ear-shattering brightness, while Channel II remained too dull and bassy to be used alone.

We acquired a 1973 Super lead—the last year before Marshall switched to printed circuit boards—for the modest sum of $1,000, made possible by a recent Dagnall replacement output transformer. Two .022 mf caps had been replaced with Orange Drops and another removed altogether in a futile effort to reduce brightness and gain—other-wise, the original Super Lead circuit remained intact and unmolested. Our plan was to run the amp at approximately 60 watts with just two EL34s, requiring the amp to be set at half the rated speaker impedance of our 8 ohm 4×12 Avatar cabinet, loaded with two Celestion Gold Alnico 12s and two “Hellatone” 70th Anniversary G12H 30s.

As we discussed this project with Jeff Bakos, he mentioned that the 100 watt Super Leads not only sound very different from the 50 watt heads in ways that transcend a mere increase in power, but he also felt that the 100 watt Super Lead amps sound better with just two powertubes instead of the full compliment of four…“That’s very common down here—I know a lot of layers who prefer that sound.” We also consulted with Sergio Hamernik of Mercury Magnetics on a suitable replacement for the modern Dagnall OT, and he suggested the ToneClone’69 Marshall self-leaded version. “Self-leaded” means that the actual wires wound within the transformer are extended to connect directly to the amp, rather than smaller diameter lead wires being attached to the transformer internally. Installing a self-leaded version is a bit of a bitch, since you are cutting and bending much heavier gauge wire to fit in tight spaces, and the insulation must be scraped off the wires before soldering. But Jeff had been here before,and all was taken in stride.

We also noted that the original power transformer in our ’73 Super Lead was similar to those found in the early Plexi100 watt amps with plate voltages well above 500 volts.

Our amp measured 522 volts, while the plate voltage on most post-plexi 100 watt “1959” amps are usually lower—around 460 volts. The “hotter” transformer in our Super Lead produces a comparatively higher and less compressed distortion threshold, and if not for our pair of NOS MullardEL34s, we might need to be more selective about choosing current production tubes that can withstand +500 volts on the plates. Jeff was confident that JJs would hold up, less confident of Svetlanas.

We took the Marshall home and initially ran it with three spare Telefunken 12AX7s just to see if they sounded as sterile in a guitar as we had recalled in the past. They do. We could hear a distinct improvement in the mid and bass tones with the new transformer, but the bright channel remained far too bright to be used alone, even with a Les Paul. While we could manage to knock down some of the treble and acquire a decent tone with the bright channel set on “3” and the bass channel patch with the volume on “6,”pushing Channel II so far above the level of bright channel introduced an indistinct woofiness we didn’t care for. The next day we returned to Jeff’s shop for his standard Marshall 4-banger input channel mod, which simply involves moving the original .005 mf bright cap on the bright channel to the basier Channel II. We had done this before with our ’69 50 watt and a vintage PA20, and it unerringly transformers the sound of the notoriously dull Channel II to a fat, warm, musically rich and bright sound that works perfectly every time. We also replaced the two Orange Drop caps with Mallory 150s and pulled the super hi-fi Telefunkens, replacing them with NOS RCA 12AX7s—the warmest, creamiest pre-amp tube ever made.

With the Super Lead thus optimized and tweaked, its voice was transformed from an angry soprano chain saw to a classic Marshall with all of the requiste thick,rich, historic hall of fame tones at our fingertips. We could mine brilliant clean tones on “3” at a usable volume level that revealed all the gorgeous detail of the vintage patent number pickups in our Historic Les Pauls, and our Stratocaster, Nocaster and Les Paul Junior all sounded equally good. Add Fender outboard reverb and you do indeed have the Twin from Bloody Hell.As Jeff predicted, the big power supply in the Super Lead also produced a much more formidable and impressive presence than a typical 50W. Yes, the Super Lead is still a beast, tamed for your consideration and our enjoyment. But if classic Marshall tone is the sound you crave, a properly groomed Super Lead is hard to beat, and given today’s boteek and vintage amp prices, it’s a solid steal.

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Experience with Electronics and Guitar Amps?

Somewhere along the way, guitar amplifier tone got carelessly shoved into two broad categories – American and British. Fender being the quintessential American tone and Marshall being the obvious default for midrangey and reverb-less British tone. Within each, of course, there are distinct variations… Ampeg, Magnatone, Valco and Gibson, for example, are also American through and through, yet they remain distinctly different in sound and construction, and would rarely be mistaken for a typical Fender. Among British amps, Hiwatt, Sound City and Vox present equally diverse varieties of “British” tone that won’t be confused with a classic plexi Marshall head. But simply adding reverb or delay to a British amplifier will often throw listeners completely off as to its origins, while plugging into the Normal channel of a vintage Fender brown or blackface amp with the right guitar can produce an exceptional “Marshall tone.” Our recent experiment with our ’62 brown Vibrolux and a Goldtop Deluxe Les Paul with Lollar mini humbuckers rammed this point home with alarming clarity…. The point is, labels don’t always serve creativity and discovery well, and in the realm of supposed “vintage amp tone” where different examples can vary so dramatically, labels are worthless in generating much more than “skull chatter,” to quote Kye Kennedy. But, we still crave “Marshall tone,” whatever our individual perceptions of that sound may be. Well, since you asked….

ZZZZZZZZZZZZZZZT!Yes, Gear Page wankers, we just did it again. Careful you don’t get a scab on that thing… it might get infected and fall off. We’ve unearthed two alternatives that will give you the bigger, bolder version of Marshall tone that you remember from your early Jeff Beck Group, Zeppelin and Cream albums, but at a volume level you can easily live with and actually enjoy in 2008.

A reader alerted us to Roy Blankenship, oh, about a year ago, and it took that long to get an amp shipped for review and develop an interview. It was worth the wait. Blankenship builds a manageable range of custom amps in Hollywood, and he seems more interesting in building what he wants, the way he wants, than going big time. We like that. So here’s an introductory dose of Roy Blankenship – an entertaining and frank fellow to e sure. Our review follows Roy’s interview.

TQR: Can you summarize your experience with electronics and guitar amps? How did you get started initially with mods and repairs, and how did that evolve into actually building your own amplifiers?

RB: First, I was born in California. My father worked for North American Aviation, and was transferred to Columbus, Ohio when I was 6 months old. Therefore, I was born crazy, but grew up normal. My father was a genius – he could build anything, and, in fact, he built my first guitar amp. It was a single-ended 6L6 design and had a field-coil speaker. It wasn’t loud enough to play in a band, but I still have it and it still works. I later discovered the cabinet he used was the extension speaker for an old film projector.

I started playing piano when I was 3, and played brass instruments in the school band. When I was a Junior in high school, I bought my first guitar. A Kent solid body, for $49.95. I finally convinced my dad to let me buy a Health kit 2×12 solid-state kit so that I could play out, and that was my first experience with electronic assembly. I was the guy in the band who would dick with all of the equipment. We bought some PA cabinets that had JBL’s in them, I refinished and rewired them, having no idea what I was doing, but it always worked. My dad had a whole workshop including lathe and drill press, so I often did small projects and repairs, like building my own speaker box to house two Jensen 6×9 speakers for the car. I wish I would have had the vision to go into production….

I was a hobbyist for the next 20 years, getting into tube hi-fi and going through a dozen Dynaco Stereo 70s, not knowing anything about them, but doing little stuff like biasing and tube exchanges. I was employed in the music biz as a sales rep for four different firms, and the pinnacle of my career was as national sales manager of Symetrixin Seattle, WA. In 1991, I had a three-state sales territory selling body shop equipment. I stopped to see my friend, Dan Abell (of Abell Audio, 909 King Ave., Columbus, OH), best tech in the world, and drop off some octal sockets my dad had left me. Dan was all upset and expressed that his assistant had quit that day and he was in a bind because he had so much work. On a whim, I said, “Hire me. I have always loved this stuff.” “Can you troubleshoot a circuit?” I said, “Not yet, but I have people skills and can do any number of things so that YOU can work.” I knew his assistant wouldn’t answer the phone or wait on customers, so, after the first day, Dan said,“Man, I can’t believe how much I was able to get done. You’re hired!” Within two weeks, I was repairing circuits. The info that opened the door was the difference between negative and positive polarity transistors. We worked together for the next four and a half years, never an angry word between us. At one point, I wanted to live in California, so I went to a NAMM show and was hired by Groove Tubes as production manager. The learning curve was straight up – there is an incredible amount of information in that place. From there I started my own place in Santa Monica. To escape the chaos that is L.A., I moved to Florida to escape. I realized the repair biz was not a big money maker, so when two clients started encouraging me to build my own designs, I was up for it. We beat it around fora while, they finally ponied up and I built two EL84 amps.They loved them, I was shocked (they were nothing special),but they were the start. I still have number 1 that I bought back from the third owner. My experience with amp repair changed when I came to L.A. People in Ohio and Florida were happy when their amps worked… players in California wanted their amps to sound good. That opened a whole new area of learning. About the same time, I was running into a lot of overly-modified amps that oscillated themselves to death, so I added “demodification” to my business card. People would call me back and say, “Man, this amp really sounds great now,” and I would reply, “Yes, I made it stock.” The only mods I deem worthy are tone-stack bypasses on Fenders and one of two master volume circuits that actually work well. They each allow you to attenuate volume without losing everything, and they both originated with Ken Fischer, amp guru, God rest his soul. Tube amplifier technology stabilized in the mid ‘60s, and very few amp builders have done anything innovative since that time. In order to separate myself from the pack, I wanted to improve on the existing circuits. When these amps were made, people were playing clean, now everyone wants to crank them up,and in order for them to deliver, my belief is that they need a stiffer power supply. I get a lot of comments on how “loud” my amps are for a given wattage rating. One client said, “I have played a lot of these amps, they give up when you hit them, but yours sounds like a big amp.”

TQR: Describe the different models you build in terms of features, construction and tone, how they differ from vintage or other custom built amps, and what you specifically wanted to accomplish and/or improve on with each model.

RB: I build my own take on American and British circuits,and I employ a stiffer power supply than most. I am currently using turret and eyelet board construction, but a printed circuit board can be useful if made properly. The compromises made by volume manufacturers is where the “circuit board-is-bad” myth started. Proper CAD design can lend itself to a quieter, more reliable product as long as the bean counters don’t try to take a nickel out of it at every turn. All of my current product is hand-wired, and as you know, there is a lot of snob appeal and dick-measuring in this business. For example, some of my clients wonder why I do not use Clarostat potentiometers… I have tested all of these devices, and I have never had a bad Alpha pot, but the Clarostats I ordered for testing were 50% defective!

In the Leeds amp, I went with different trannies than most and a stiffer power supply; this gives it more beef. In the Fatboy, I discovered an output tranny that would allow me to use 6V6’s (for 15 watts) or 6L6’s (for 25 watts) without changing the speaker load. Though the tranny was originally designed for an 8 ohm load, it actually worked more efficiently at 16. Overall, using Mercury trannies has been one of the best decisions of this whole venture. Now when I hear an amp with any other tranny, they sound flat. I took one of my amps to visit a friendly competitor, he played it and enjoyed it, then fired up his own amp, and it sounded flat. He was looking at his amp as if,“Hey, what’s going on here?” I think that was his first side-by-side comparison and he could hear the difference, much to his own chagrin.

TQR: What inspired the use of a Variac with the VariPlex? Why not just build a master volume circuit?

RB: We wanted to create a cranked-up Marshall sound at lower volumes, but people have time and again expressed their dissatisfaction with the attenuators on the market and the smashed sound of a bad master volume circuit. I credit Dave Friedman of Rack Systems with the concept and the prototyping. We tried five different kinds of coupling caps, different types and brands of resistors, different trannies…you name it. Eddie Van Halen popularized the whole Variac concept, so we modified the circuit so you could go from full tilt boogie down to 1 watt and the amp would not shut off. We have sold 40 of those amps with no marketing other than clips on a forum. We are now introducing a similar amp with a master volume for those who want it whisper quiet, but saturated. There are two master volume circuits that I know of that sound great even when turned down to speaking levels. We are using one of those and a few other mods in the new model, the Custom 45.

TQR: You describe a process on your web site in which you A/B’d the VariPlex with a friend’s ’68 Plexi and you didn’t stop tweaking the design until 10 out of 10 guitarists chose the VariPlex in a blind test. Can you elabo-rate on how those tests progressed and the changed to the circuit that you made to achieve those results?

RB: I could, but I won’t.

TQR: In your experience, how much variation in tone and component values, including transformers, have you observed in vintage Marshall amps? Isn’t it necessary to listen to a lot of different examples and then choose an exceptional amp as a benchmark?

RB: Yes. We already had “the Holy Grail” plexi in house, so we compared to that one. Most amps will respond to love, but there are some that are just exceptional. The reason for this amp-to-amp variance is manufacturing tolerances. If your trannies are built with plus or minus 20% tolerances, that means your amp could vary as much as 40% from sample to sample.

TQR: The VariPlex doesn’t sound “new” in the sense that it isn’t shrill or bright and sharp like some replica Marshall amps. How did you accomplish this?

RB:That’s my secret.

TQR: How long is the wait for one of your amps once it has been ordered?

RB:We have Carry-Ons in stock for the first time. Generally, we like to say 3-4 weeks just to be safe. Most of this is the gray area of vendor delivery on cabinets.

TQR: What’s ahead? What do you want to accomplish in the future?

RB: I want to be a thorn in someone’s side so they will offer a butt load of dough, I will sign a non-compete, and go away. Then, I can sit on the beach and light my cigars with $100 bills and sip pina coladas. The funniest thing about that picture is that I don’t drink OR smoke. Actually, we are introducing a bass amp shortly. As we gain more exposure, I am sure we will have enough to do. I am happy with people’s response to my products. I do not want to get huge, and I will probably not offer many more models – it gets too confusing. But thanks for considering me as a worthy contributor to your magazine. www.BlankenshipAmps.com (818) 530-8853

Our experience with “vintage Marshall tone” was formed with two stout examples that we were fortunate enough to own and play for years. The first was actually a late ’60 Park ’7550 watt head, followed by a metal panel 1969 Marshall50 watt. Both amps displayed the classic tone, smooth distortion and touch-sensitive dynamics we love to love and eagerly oozed the warmth and dimensionality that reissues lack. This isn’t complicated…. We’d simply drag a newish Marshall clone of some sort into the music room, compare its sound to the old one and invariably say, “Not bad, but this one sounds and feels better.”

When we fired up the Blankenship, however, not only did it sound richer and fuller with more depth than our old Marshalls, but the tone controls actually produce changes in EQ that allowed the amp to achieve a level of versatility that has always been sorely lacking in the originals. And then, of course, there is the nifty Variac that allows the VariPlex to be played at nominal volume levels with no audible deterioration in the responsiveness or tone and the amp. Essentially equipped with features that mirror an original Plexi, the VariPlex is a 2 channel/4 input design with presence, bass, mid and treble controls. Channel 1 is the bright input; channel 2 is more bassy, and the two can be jumpered and mixed to taste.

We took our time developing an impression of the VariPlex, playing it for over two months. Bottom line – it produces an authentic, old-school Marshall voice with better EQ, clarity, and fresher, more vivid harmonic content. Its voice is exceptionally smooth, yet capable of acquiring the melancholy edginess of an early Clapton recording by simply managing EQ, and the Variac as a master volume control works brilliantly. The VariPlex impressed us as a near-perfect example of an overbuild, hand-wired, low-production amp inspired by arguably the best efforts of Jim Marshall and company, circa 1968. Just as the Balls M18 became our modern benchmark for low-powered, classic Marshall tone, so goes the Blankenship VariPlex in the 50-watt range. If there is a better-sounding modern alternative toa vintage Marshall, we have yet to hear it.

We also admired the neat, clean and easy-to-read design of the VariPlex silver control panel, somewhat reminiscent of our old Park. Among all the clones being cloned with Mojo boxes, this amp is a visual standout. And as far as internal build quality is concerned, let the pictures speak for them-selves. In all respects the VariPlexis a solid piece of work,returned to the builder with as much regret as any amp we have ever reviewed. In fact, we’re still thinking about it. Plex forth….

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Restoring Old Amps and Transformers

Finding and restoring old amps and cabinets is a slow process that demands patience. From the time we first began trolling eBay, ultimately scoring a tweed Vibrolux and Tremolux, to final delivery of the aged cabinets and assembly of the amps, six months had easily passed.

We first found and bid on a ’58 Vibrolux in September ’06. Sold by an eBay seller in Texas, it had been recovered in reddish-brown cloth similar to the stuff used to cover hymnals or a bad ’60s pleather recliner for the double-wide. Otherwise, it was pretty straight, with the original blown Jensen P10R intact, and the original transformers, caps and resistors. The inside of the cabinet had been painted black, but the cabinet, grill cloth, baffle and control panel were otherwise intact, and the wooden tremolo footswitch was included. We bought the Vibrolux for $1,590.00 with 4 bids placed.

Inspired by Larry Cragg’s detailed description of Neil Young’s tweed Tremolux, a1958 Tremolux surfaced on eBay in November 2006, and we scored it for just $1,082.00 from a seller in San Francisco. We suppose this amp was so cheap because the output transformer had been replaced, and the cabinet had been completely stripped and stained mahogany brown. The original speaker mounting screws in the baffle board were about to fall out. However, the original Tremolux circuit was well-preserved, and a small strip of tape remained in the chassis signed in a delicate hand by “Lilly” – one of the many women in Fullerton employed to assemble amplifiers like the Tremoluxin 1958. God bless her. The Tremolux also arrived with the original wooden foot switch.

The Vibrolux kicked some serious tail right out of the box. We send the original Jensen P10R to John Harrison at A Brown Soun (www.abrown.com) for a re cone, mounting a1965 Jensen C10Q sent by Larry Pogreba in its place – a very stout choice and original equipment in early blackface Vibrolux Reverb amps. Like the Tremolux, the tremolo circuit in the Vibrolux required some TLC,with four caps needing replacement to restore the swampy oscillator circuit to full wobble-weave. We also replaced all the newish tubes with NOS RCAs, Philips and GEs. Once we had the amp mounted in the restored and aged cabinet, we were throwing down hard with our No caster nightly, wallowing in the big sound coming from such an innocent-looking little biter, when the original output trans-former gave it up in a final, glorious gasp. A quick call to Mercury Magnetics produced a ToneClone replacement within a week and we were soon back in business,sounding better than ever.

The 10 watt, 3-input ’58 5F11 Vibrolux is housed in the same cabinet Fender used for narrow panel tweed Deluxe– a fat little featherweight with greasy tremolo and a smooth bark tailor made for a Telecaster. And 10 watts may be the perfect power notch for low-volume home recording and jamming – crystal clear, bright and drenched in gorgeous Fendery overtones at low volume (3-5), and absolutely on fire from 7-10. In all respects, the 5F11 Vibrolux is a big amp in a small package worth pursuing for its outstanding tone and personality at truly usable volume levels.

We were amazed by how Gregg had managed to remove every trace of black paint that had been sprayed inside the cabinet, and his aging job, complete with three coats of amber stain and lacquer, faint water stains along the bottom,worn seams and corners, aged L&L leather handles and scorch marks from the power tubes on the inside of the back panel were flawlessly conceived and applied. Hopkins even recreated the original tube chart with a 1958 date code after requesting that we send him the chassis number and power transformer EIA code for production verification. When we brought the restored Vibrolux to Jeff Bakos’ shop (www.bakosampworks.com), he looked it up and down as it sat on the floor of his workshop, peered into the back and said, “That is totally sick.”

The ’58 Tremolux provided a further study in what can be involved buying 40 year-old amps. Upon arrival,the amp was really smokin,’ even with the Jensen hangin’ off the baffle board. The tremolo was DOA, however, so while the stripped cabinet was getting the spa treatment in St. Louis, Jeff replaced two caps in the trem circuit, we replaced the already replaced output transformer with another from Mercury Magnetics, and stored the chassis away until we received the finished, aged Tremolux cabinet from Gregg in late March ’07.

The 5E9A (’55-’56) and 5G9 (’57-’60) Tremolux are housed in the same taller, wider cabinet Fender used for the 1×15 narrow panel tweed Pro,and the later 5G9 circuit is quite different from both the 5E3 Deluxe and the ’55 5E9ATremolux, being fixed rather than cathode biased, employing a long-tailed phase inverter common to the bigger narrow panel tweed amps, and the addition of an extra filter cap and choke enabled the power to be increased from 15W to 18W in 1957.

Compared to the narrow panel tweed Deluxe and the 5E9 Tremolux, the 5G9 Tremolux develops more volume and headroom, and should you chose to replace the 12AY7 preamp tube with a 12AX7, gain is further increased (it’s already righteous with the 12AY), while the bigger 10” x22” x 10” cabinet produces a much rounder, warmer tone with superior ambience and presence. In the month or so since we’ve had the Tremolux put together in the restored cabinet, a new Tung Sol6V6 blew (after we had opted not to use a couple of spare ’50s RCAs for safety – they are in the amp now and killin’ us with bogs of good thang),and we just took the amp back to Jeff when it began spitting some nasty distortion provoked by low frequencies from the guitar. Turned out to be a few bad solder joints.

Like the Vibrolux, Gregg had stopped short of creating a “3-legged dog with an eye patch,” taking the aging to a moderate level with frayed edges and seams on the amber tweed, a single beer can ring on the top with a foam overflow stain running down the grill cloth, a slight orange stain on one side from pine knot bleed, and assorted scuffs and light abrasions. He also repaired the baffle-board, filling in the old holes for the speaker mounting screws.

We hate doing this to you (again), but truth be told, we have to give the nod to the Tremolux as the most toneful and inspiring amp in its power class (18 watts)that we have ever heard or owned. It’s ascension to Numero Uno status was a bit of a surprise, but then again, we considered the initial source of our inspiration for finding one – Neil Young, via his tech, Larry Cragg, and in hindsight we should have expected as much. With all the attention paid to the tweed Deluxe as the big time bonerizer of the tweed family, the Tremolux seems to have been overlooked for the usual reasons…. In the nose-to-butt-crack daisy-chain march to mediocrity, the masses never seem to acquire a view beyond the first lazy dumb-ass directly in front of them. In the immortal words of the great hoosier educator and smack-down artist Earl Dosey, they are “stepping’ over dimes to pick up nickels.” Let’s hope the lemmings continue to keep their heads down.

So here’s the move…. Sad as we are to share this, our strategy was as obvious as it seems. Forget about original speakers, don’t let a replaced tranny run you off (we’ve never replaced one with a Mercury that didn’t sound better than the original), and deliberately track down the fuglies told girls you can find from the tweed era. Busted baffle boards? We luv that….Ricky-ticky cabinets are good, and the coverin’ don’t matter. What you want is a beater with a totally neglected chassis and as many of the original fat Astron caps and original resist or present as possible. Yeah, some of them may have to be replaced, but it’s far better to allow a prudent and judicious amp tech determine that rather than buying an old amp that has been raped by a hard chargin’ cowboy hooked on Sprague Orange Drops.Buy one of those and your old amp will sound new,never to sound old again, and that’s most definitely not the play you want to make here. A little component drift is good.

There is luck involved, too… not all vintage amps were created equal. Some of them left the birthing bench endowed with incredible tone – a happy accident created by the melding of variable components that resulted in extraordinary sounds. Others were created by the same roll of the dice, but with a different outcome altogether – mysteriously dull, flat, or simply lacking whatever you wish to call it… that tone, mojo, bloom, the harmonic complexity of your first Schlitz, depth, fatness… whatever. To experience the blissful afterglow of unanticipated discovery, you must be willing to risk something, which is another way of saying that faith must be exercised in the absence of a guarantee. In this respect, buying old amps is a lot like life itself…. The greatest obstacle to discovery is the flawed perception of an impossible challenge. And the window of opportunity is closing on these great old amplifiers faster than you may think. Like vintage guitars, the best old amps are being taken out of circulation by col-lectors willing to pay prices that are based on potential future value (more than they are worth today, perhaps, but less than they will be worth tomorrow). For you, hombre, the time to bust a move is now.

 

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Lindy Fralin Guitar Amp

On the other hand, if you’re inspired to run down some musty Fullerton tweed, we’ll assume you are also fully prepared to bend over ’til it hurts. Well, know this… there is little correlation between the absolute certainty that you will pay a considerable premium for an unmolested, vintage tweed Fender amp today and an iron-clad promise of awe-inspiring tone. As we’ve said before, the market value for vintage instruments and amps doesn’t carry an implied warranty… You are paying a premium for a collectable amp or guitar based solely on its collectable value; the extent to which it may fulfill its intended purpose to your dismay or delight is a crapshoot unless of course you are able to try before you buy. This didn’t matter much when tweed was $50 trash, but throwing down a minimum of two grand today is no joke.

There  is less risky and expensive route on the quest for tone, which is to buy a new amp made by people who have figured out how to actually design and build exceptional sounding tools with repeatable consistency. Perhaps you are the type who is risk-adverse, unwilling or afraid to adopt an old amp that may need to be fortified by skilled hands at $75/hour. Well, we’ve found another stellar new amp, and it carries the familiar name of Lindy Fralin. No, Fralin didn’t personally build it, but it is built to his specifications and personal preferences by Vintage Vacuum Tube Amps in Waldorf, Maryland, which is close enough to Lindy Fralin’s shop in Richmond, Virginia to have fostered a very productive collaborative relationship.

Lindy Fralin is one of the best known custom pickup makers in the country and an experienced guitarist with an extensive collection of vintage amps. But despite his fat collection, he found himself craving things that weren’t collectively found in any one of his vintage amps. Fralin wanted clean headroom at volume levels that could hang with a band in a small to medium-sized club. He also insisted that such an amp be portable enough to be effortlessly carried up and down the stairs in his house and back and forth to gigs. He wanted reverb, and a smooth, musical voice that was compatible with all of his many guitars, and the amp had to be a looker in a dignified, classic sense — not too plain or gaudy in an effort to appear different or unique.

Fralin and the two founders of VVT spent months working on various prototypes, which involved several rounds of experimentation with custom transformers built by Mercury Magnetics. Once the basic layout was determined, different caps, resistors, tube configurations and speakers were tested, and work continued until Fralin finally heard the sound and feel he had been craving in his head.

The result is a remarkable 30 watt, 1×15″ cathode biased beauty that can run on dual ^L^s for maximum headroom or 6V^s for slightly faster breakup. Features are simple and straightforward with just a bright switch, volume, treble, bass and reverb controls. We ran the Fralin through its paces with all of our usual test guitars, and we were consistently impressed with the sound of them all, as well as the hug spring reverb, loads of clean headroom and subtle distortion at higher volumes that adds sustain without substantially altering the beauty of the fundamental note. As we played Fralin’s amp, reoccurring visions of Peter Green’s brilliant tone came to mind… clean, exceptionally smooth, warm and round with the perfect edge, enabling the guitar to alternate between sweetness and urgency as dictated by the song. Our impression was also echoed the the other guitarist in Delta Moon, Tom Gray. Tome plays slide using acoustic Weissenborn-style guitars loaded with a Sunrise soundhole pickup. Prior to hearing the Fralin, Tom’s stage rig consisted of a Blackface Pro reverb head paired with a separate 1×15 cabinet and an Avalon preamp identical to that used by Clapton for his acoustic guitars, live. After Tom played the Fralin amp sent to us for review, he bought it, and now no longer even needs the Avalon.

Aside from looking good and weighing barely 30 pounds, Fralin’s amp incorporates an “Integral Beam Diffuser” — a wooden cross-piece cut out of the baffleboard that bisects the speaker behind the grille cloth, diffusing the sound waves as they come off the speaker cone. Fans of larger ’60s Supro amps may be familiar with a similar cross-piece found in those amps, and it does indeed produce a sound that is less beamy and linear (especially helpful when you’re crammed on to a tight stage with the amp on the floor). You really can hear it better.

VVT’s Fralin amp is simply a compact, lightweight, heavy-duty gig monster, and it definitely deserves your attention. The Weber Classic Alnico 15 thrives on every frequency you can throw at it in the Fralin, and we recommend this amp without reservation for blues, heavy rockin-blues, jazz, country, swing… everything but hard rock and metal. For that, check out the other amps built by VVT.

Source: https://mercurymagnetics.com/pages/news/ToneQuest/_2006/TQRDec06.htm

Transformer Replacement

Article: Let’s Ask Budda with Jeff Bober of Budda Amps

Q: I’ve got an SR Blackface ’66 amp, all original. The sound is very thin, weak and trebly. There’s nothing wrong with any of the tubes, and it has been biased correctly. I’ve tried the amp through different speakers but found the same result. The amp hasn’t been played very much over the years. Can it be old, dried-out capacitors that make the amp sound like this? Can a complete replacement of the capacitors really improve the sound – meaning to give it more twang and bottom end, or “life”? – Tobbe Sweden

A: Beautiful amp. One of my favorites… except, of course, for a Budda!

I’m assuming both channels of the amp are thin and weak. If it were only one channel that sounded bad, I would tell you that the 100K resistor in the tone stack of that channel was probably open. This would also disable the Middle and Bass control, but I’m going to assume that all the amplifier controls function properly. Since you also mentioned that the amp has been properly biased, I have to assume that the primary sections of the power supply have the correct voltages.

Considering the amp’s age and the possibility that it might have been sitting idle for some time, a power-supply cap job is probably a good idea. This might not be the source of the problem, but once any other repairs have been made it will make the amp sound stronger and tighter. Make sure the values of the power-supply resistors are checked after the filter caps have been removed. A power-supply resistor that’s substantially out of tolerance can cause degradation in tone, but usually it won’t be as drastic as the symptoms you’re describing. And don’t forget to have the bias supply cap replaced. A weak cap in the bias supply will give the amp some additional unnecessary hum. You might also want your tech to do some normal maintenance on the amp, such as cleaning all of the tube sockets and controls while he’s in there. A very dirty tube socket, especially in the phase inverter, can really suck the life out of the amp. If the amp still isn’t right after the maintenance and power-supply build, it’s time to start looking elsewhere.

Okay, let’s look at some other possible causes for an anemic Fender amp. The first thing I’d look for would be the ground connections from the circuit board. These are the buss wires that come off the circuit board behind the controls and solder to the brass grounding plate that runs under the control panel. I’d check all of these connections, but there’s a particular one that seems to be the most frequent offender. It comes off the board in the area of the tremolo and phase inverter circuits behind the tone controls for Channel 2. For some reason this solder connection tends to break, causing the phase inverter to lose its grounding. That makes the amp lose substantial power and sound thin. If any of these ground connections is broken, it takes a good deal of heat to re-solder them. So, you’ll need to use a high-wattage soldering iron or gun. If all these ground are intact, the next thing to check would be the 100-ohm (brown/black/brown) resistor in this same area. It’s the only resistor in the area that is positioned horizontally on the circuit board. It also typically suffers from a broken solder connection and will yield the same low-power situation. Re-solder the resistor, and you should be good to go. If not, it’s time to start looking at the other major cause: a bad output transformer.

The best way to determine if the output transformer is bad is to simply substitute it with one you know is okay. A good way to check it is to simply unsolder the leads coming from the original transformer and attach a replacement using clip leads. If you can’t come up with a Super Reverb transformer to try, a Twin Reverbtransformer will work well for the test. If you need a replacement transformer, I have to recommend (as I have in the past) Mercury Magnetics. Their Axiom line of transformers should have just what you need. They can be found at www.MercuryMagnetics.com.

I hope you can make your Super super again.

Source: https://mercurymagnetics.com/pages/news/PremierGuitar/MusiciansHotline-2.htm

FBFBM-P

Blackface — no 5V winding — solid state rectifier — Fender #125P7D

FBFBM-P-E

Blackface — 5V winding — #125P5D export — Universal Voltage Primary

FBFPP-MM

Blackface — lowest B+ — 250-0-250

FBFCP-M

Blackface — Lower B+ — 325-0-325

FBFPP-X-U

Blackface — 50V bias tap — 360-0-360 unloaded B+ — Universal Voltage Primary

Fatstack — 2 1/2″ lamination stack — ok to use with two 6L6 — hole spacing 2″ x 2 1/2″

FC-BAND

Blonde, Brown, Blackface, Silverface

FC-BASS

Blonde, Blackface & Silverface  — 3 Henry — 2 13/16″ Mounting Centers

FC-CON

Brown, Blackface

FC-CONII

Mid ’80s Blackface — Upgrade!

FC-PRO

Brown, Blackface, Silverface

FC-SHOW

Blonde, Blackface, Silverface & Dual Showman

FC-SUP

Brown, Blackface, Silverface — 3 Henry / 200 mA Choke — Original Fender Part #125C1A

2 13/16″ mounting centers

FC-TREM

Blackface

FC-VIBROV

Brown, Blackface

FBFPRO-P

Blackface — #125P5D

FBFVV-P

Blackface era — #125P5D — mounting holes 2 3/4″ x 3 7/16″

FBFPRO-P-240

Blackface — #125P5D-X — Universal Voltage Primary

FBFVV-P-240

Blackface — Universal Voltage Primary

FDR-PRI

Upgrade for ’65 & ’68 Reissue Deluxe Reverb — bolt hole spacing is 2 1/2″ x 3 1/8″ — 2″ stack

FBFVL-O

Blackface — 8Ω tap

FBFVL-OM

Blackface — 4, 8 & 16Ω taps

FBFBM-OM

Blackface — 4, 8 & 16Ω taps

FBFTR-O

Blackface

FBFVLR-O

Blackface Reverb — 4Ω tap — 125A6A (022848)

FBFS-O40MM

Blackface Reverb — 2, 4 & 8Ω taps

FBFCO-M

Blackface — 4, 8 & 16Ω taps

FBFP-85-U

Blackface — Universal Voltage Primary

FBFPC

Blackface — add this choke to your amp for improved tonal richness

FBFCP-240

Blackface — 220V, 230V & 240V primary

FBFPP-240

Blackface — 220V, 230V & 240V primary — #125P1B

FBFVC-P-240

Blackface Vibro — 220V, 230V & 240V primary taps

FBFPP-100

Blackface — single 100V primary tap

FBFVIBROV-P

Blackface Vibroverb Custom — single 120V primary — Drop-In Upgrade!

FBFVIBROV-P-U

Blackface Vibroverb Custom — Universal Voltage Primary — Drop-In Upgrade!

FBFVBSON-RI-P

“Custom” — ’95-’96 Blackface — #037610 — Upgrade!

FBFVBSON-RI-P-240

‘”Custom” — 95-’96 Blackface — 220V, 230V & 240V primary — #049181 — Upgrade!

FBFCO

Blackface — #125A35A

FBFPO

Blackface — #125A10B — #022913

FBFS-C3H

Blackface Era 3 Henry / 200 mA Choke — Original Fender Part #125C1A

2 13/16″ mounting centers

FC-TWIN

Blonde, Blackface, Silverface — #125C1A — 3.0 H, 95 Ω DC resistance

Mounting centers are 2 13/16″

FBFBMO-M

Blackface — 6K primary — 4, 8 & 16Ω taps

FBFBO

Blackface Era — 125A6A

FBFPRO-O

Mid 60’s Blackface — single 4-ohm tap for 2×12 — #125A6A

FBFVO-40

Blackface — 8Ω tap — #125A7A

FBFVV-OM

Blackface — 4 & 8Ω taps

OFBF-20

Blackface — 20 watt with 8 Ohm Secondary.

OFBF-20-4-8

Blackface — 20 watts with 4 & 8 Ohm taps

FBFVO-40-M

Blackface — 4, 8 & 16Ω taps

FBFCP-MM

Blackface — Low B+ — 250-0-250

FBFCP

Blackface Champ — #125P1B — Flat mount 2″ x 2 1/2″ hole spacing

FBFPP

Blackface — #125P1B — stock size, uses 1″ lamination with 1 1/4″ tall stack

Silverface amps had same PT, but marked as #022772 (early) or #L010020 (later)

Mounting hole spacing is 2″ x 2 1/2″ — ** Also works in Fender’s reissue ’65 Princeton Reverb amp

FBFVC-P

Blackface Vibro Champ — #125P1B — Flat mount 2″ x 2 1/2″ hole spacing

FBFVO-40X

Blackface — 2, 4, 8 & 16Ω taps — extra iron OT

F-DELUXE-FS-OM

6.6k primary — 2, 4 & 8Ω taps — 4″ Mounting Centers

FBFPR-P-240

Blackface — lower B+ — 220V, 230V & 240V primary

FBFPP-M

Blackface — 50V bias tap — lower B+ — 325-0-325

Mounting hole spacing is 2″ x 2 1/2″ — 1 7/8″ lamination stack, taller than stock

FBFPP-S

Blackface — 50V bias tap added — 360-0-360 unloaded B+

Has taller 1 7/8″ lamination stack — mounting hole spacing is 2″ x 2 1/2″

FBFPP-S-DP

Blackface — 50V bias tap — 360-0-360 unloaded B+ — Universal Voltage Primary

FBFCT-O

Blackface — 2Ω tap

FBFBM-OT-4

For Late Blonde (’63-64) & Blackface era amps — 1-1/4″ stack — #125A13A — Single 4 ohm tap

Exact clone & dimensions of stock OT — bolt hole spacing is 2″ x 3 3/8″ with Especial bracket

FBFS-O40

Blackface Super Reverb — 2Ω tap — #125A9A (022855)

Mounting holes are 2″ x 3 3/8″

FBFS-O40M

Blackface Reverb — 4 & 8Ω taps

FBFBM-O

Blackface — 1-1/2″ larger stack — #125A13A

FBFVL-PS

Blackface — 294-0-294 unloaded B+ — 6.3V @ 6A — 5V @ 3A

OFBF-85

Blackface — 85 watts into single 8 Ohm tap — #125A30A

FBFVL-P

Blackface — #125P26A  — Also for Vibrolux Reverb amps

Flat mount type — bolt hole spacing 2 1/2″x 3 1/8″

FBFVL-P-240

Blackface — 220V, 230V & 240V primary

FBFVL-PM

Blackface — lower B+

FBFVL-PM-U

Blackface — Universal Voltage Primary — lower B+

FBFVL-RI-P

Blackface — reissue — #036958 — Upgrade!

Flat mount type — Bolt hole spacing 2 1/2″ x 3 1/8″

FBFVL-PM-240

Blackface — lower B+ — 230V & 240V primary

FBFVL-PMM

Blackface — lowest B+

FBFTO-85M

Blackface Reverb — 4 & 8Ω taps

FBFTO-100M

Blackface — 100 watt — 4, 8 & 16Ω taps — smaller stack

FBFTO-85

Blackface Twin Reverb — #125A29A (022889)

FBFVL-RI-P-240

Blackface — reissue — single 240V primary tap — Upgrade!

FBFBP-50

Blackface — no 5V winding — solid state rectifier — Fender #125P7D

FBFBM-PM

Blackface — lower B+

FBMP-50M

Blackface — 5V & bias windings — #125P5D

FBFS-P40

Blackface Reverb — #125P5D  (#022798) — mounting holes 2 3/4″ x 3 7/16″

FBFS-P40M

Blackface Reverb — lower B+ — 344-0-344 unloaded

FBFTO-100

Blackface — 100 watt — 4, 8 & 16Ω taps

*Confirm mount style needed when ordering

FBFS-P40X

Blackface Reverb — lower B+ — 325-0-325 unloaded

FBFP-85

Blackface — #125P34A (022756) — Correct for the Dual Showman also

FBFP-85-MT

Blackface — 230 & 240V primary

FBFTP

Blackface/Silverface Twin Reverb amp — #125P34A (022756)

Flat mount — bolt hole spacing is 3″ x 3 3/4″

FBFBP-50-240

Blackface — 100V, 120V, 220V, 230V & 240V primary

FBFTP-U

Blackface — Universal Voltage Primary

FCONII-P

Mid ’80s Blackface — #018302

FBFS-P40-100-240

Blackface Reverb — Universal Voltage Primary

FBFS-P40M-240

Blackface Reverb — lower B+ — 344-0-344 unloaded — 230V & 240V primary taps — Upgrade!

FCONII-P-U

Mid ’80s Blackface — Universal Voltage Primary

FTWIN-RI-P

Blackface Reverb for ’65 reissue — #037610 — Drop-in Upgrade!

FTWIN-RI-P-240

Blackface Reverb for ’65 reissue — 220V, 230V & 240V primary — #049181 — Drop-in Upgrade!

FBFPP-M-U

Blackface — 50V bias tap — lower B+ — 325-0-325 — Universal Voltage Primary

FBFTO-100-UL

Blackface “Evil” Twin — 100 watt with UL taps — 4, 8 & 16 Ohm secondary taps

FBFTO-85MT

Blackface — 4, 8 & 16 Ohm taps

FBFDS-O

Blackface Showman / Dual Showman — #125A29A (022889)

Sizes vary – please call before ordering.

FBFDS-OS

Blackface Dual — 4 & 8 Ohm taps — Upgrade!

FBFVLR-O-8

Blackface Reverb — 8 Ohm tap

FBFPRO-OS

’60s Blackface — 4 & 8 Ohm taps

FBFS-16

Blackface era — single 16 Ohm tap — Upgrade!

FBFSUP-OM

Blackface Reverb — 4, 8 & 16 Ohm taps

FBFVIBROV-OM

Blackface Vibroverb Custom — 4, 8 & 16 Ohm taps — the SRV-style over-sized OT — Drop-In Upgrade!

FBFVLR-OS

Blackface Reverb — 4, 8 & 16 Ohm taps — Upgrade!

FCONII-OS

Mid ’80s Blackface — 2 Ohm tap — Upgrade!

FBFVLR-OC

Blackface Reverb — 4 & 8 Ohm taps — Upgrade!

FCONII-O

Mid ’80s Blackface — 4 & 8 Ohm taps — Upgrade!

FBFPROR-FS-O

Blackface Reverb — 2 & 4 Ohm taps — Upgrade!

FBFVLR-OM

Blackface Reverb — 2 & 4 Ohm taps — Upgrade!

FCONII-OM

Mid ’80s Blackface — 2 & 4 Ohm taps — Upgrade!

FBFVC-OM

Blackface Vibrochamp — 4, 8 & 16 Ohm taps

FBFPO-M

Blackface — 4, 8 and 16 Ohm taps — #125A10B — #022913

FBFVIBROV-O

Blackface Vibroverb Custom — single 8 Ohm tap — the SRV-style over-sized OT — Upgrade!

FBFTO-100X

Blackface — 4, 8 & 16 Ohm taps — Upgrade!

FBFVIBV-O

Blackface — 4 & 8 Ohm taps — the SRV-style over-sized OT — Upgrade!

F-SUP-O-FS

Blackface Reverb — 6k primary — 4 & 8 Ohm tap — Upgrade!

FBFDS-OM

Blackface Dual — 2 & 4 Ohm taps

FBFDR-O-FS

FatStack Upgrade! — 8k primary — Single 8 Ohm Secondary

FBFPROR-O

’60s Blackface Reverb — single 4-ohm tap — #125A6A

FBFPRO-OM

’60s Blackface — 2, 4 & 8 Ohm taps

FBFVC-O

Blackface VibroChamp

FBFBNDM-OM

Blackface — smaller size — 4, 8 & 16 Ohm taps

FBFBO-S

Blackface — single 4 Ohm tap — four screw mount

FBFB-OX

Blackface — 4 & 8 Ohm taps — Oversized Upgrade!

FBFBM-OX

Blackface — single 4 Ohm tap — Oversized Upgrade!

FBFS-O40-FS

Blackface Super Reverb — single 2 Ohm tap — Fat Stack Upgrade!

Mounting holes are 2 1/2″ x 3 3/8″

FBFBP-50-U

Blackface era – With Universal Voltage Primary

FBFS-P40MM

Blackface Reverb — Lowest B+ — 285-0-285VAC unloaded

© Mercury Magnetics
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