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?


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