Transformers are a Crucial Piece of the Puzzle

After a hiatus of 45 years or so, Fender has been carefully re-entering the business of building hand-wired tweed amplifiers with the resurrection of the narrow panel ’57 tweed Twin and the ’57 Deluxe. Of course, there are scores of small amps that have been inspired by the Deluxe, and many more 5E3 knock-offs being built today in the “subbooteek” cottage industry comprised of solo solderers who build in their spare time and often put their work up on eBay. For some cost-conscious players, a tweed Deluxe for $600–$800 is a deal that cannot be refused—even if the amp was wired up by an unknown tonehead on a basement workbench in Akron. But Fender is Fender, and while they chose to ignore the thriving boutique market for hand-wired tweed circuits that blossomed in the early ’90s with the appearance of Victoria, they have not forgotten how to put an amp together, and in the case of the Deluxe sent to us for review, it stands apart from all the rest with a very unique voice.

We asked Fender’s Shane Nicholas and Sergio Hamernik at Mercury Magnetics to explain the process of natural selection that evolved during the development of the ’57Deluxe….

TQR: Describe the process in which your design team evaluated various vantage examples of the 5E3 Deluxe, and how widely the actual sound of the vintage amps you listened to varied, specifically?

Shane:There are several guys here at Fender who own old amps, and we also have friends who do. When we were ready to begin the’57 Deluxe project, we brought in a few original vintage examples, and a couple of “boutique” versions of this type of amp. We listened to all of them with various guitars, and listened to each amp chassis hooked up to the others’ cabinets. Keep in mind that every amp—especially 50-year-oldones, will sound a little different than another one of the same model. It’s pretty well documented that Leo Fenders some times changed components “on the fly,” while the official schematic documentation would be updated later. My old Deluxe might have been built with some different stuff than yours, even though they were both “stock” 1957 5E3models. Then add in aging, abuse, repairs, etc., and it’s a wide target that needs to be narrowed. For example, we had one amp here that was much more distorted sounding than the others, so unless you are only laying 1951 Howlin’ Wolfstuff, you probably wouldn’t like that amp as much. For me, the ideal is an amp that gives a beautiful clean tone with the volume set low, and a dirty, harmonically rich tone with the volume set high. You should also be able to set it on, say, “5” and control the amp’s distortion by simply varying your pick attack. We decided that one of the old ’57s was the most desirable example of a 5E3 Deluxe, and we used it as the golden sample.

Once we got to this point, project engineer Nick D’Amato really got down to business. The final schematic and components we chose were basically picked so the prototype would sound as close as possible to our golden sample amp. Obviously, we use new parts, not 50 year old stuff from a flea market or whatever. We also had to make a few changes in order to pass modern worldwide safety regulations; things like shielding, ground wires, and the three-prong power cord, which negated the use of the old ground polarity switch. We put a Standby switch in its place, which is a good thing. These changes don’t really affect tone, but they do reduce hum and improve playability.

We also decided to go with 12AX7s in the preamp, even though the originals were designed with the 12AY7 in the front end. Our thinking was, not only is the 12AY7going to be tough for us to get in quantity, but many players in fact prefer the 12AX7s higher gain. If you are playing ZZ Top stuff, for example, you’ll probably prefer this. The12AY7 will work, however, so some owners will buy one and stick it in their amp.

The transformers are also a crucial piece of the puzzle. We auditioned quite a few prototypes, and some of them were too efficient or too distorted, etc. One of the vendors we contacted was Mercury Magnetics, whom we’ve worked with in the past They sent us five different power and output samples, each based off an original transformer set found in a vintage Deluxe amp. During A-B tests, one of these closely matched the OT in our golden sample amp. We worked with Mercury to make a few tweaks, and soon we were positive we had the right transformers.

TQR: How many different types of speakers did you consider?

Shane: Well, the original Jensen in my old Deluxe really sounds and looks perfect, like you’d expect. We found that the new Jensen P-12Q sounded close enough, so we stopped looking. In my ten years at Fender, I have discovered that no matter what speaker we supply in a tube amp, a certain percentage of customers are going to try something else. Celestion, Jensen,Eminence, and boutique guys like Weber all have their supporters and detractors. It’s human nature to tinker with your machinery, and a speaker swap is one of the easiest mods you can do to an amp.

Now, having said all that here’s where it gets fun. One of the boutique amps we tried happened to have a Celestion Blue Alnico speaker in it, and it sounded very good. So we tried that speaker with our prototype 5E3 amp, and said,“OH MY WORD!” I had heard that speaker before in different amps, but this combination was stunning. The amp became a lot louder, for one thing.We thought for a minute about using this speaker in the ’57 Tweed reissue, but it’s not really the authentic, original sound or look. It’s also a lot more expensive. So, we remained sold on the Jensen, but when we developed our limited edition, black lacquered version—the Fender 57 Amp—we decided to equip it with the Celestion Blue.

TQR: What are the unique challenges involved in building hand-wired amps, compared to those with a printed circuit board?

Shane:Making it look and perform like the old amp while using readily available parts that we can buy in quantity. I am a stickler for performance, but if our customers didn’t care to look inside, we wouldn’t worry about the looks of the components and wire so much. For example, Alexander Dumble told me he likes our new ’57 Deluxe, and was surprised that we used such heavy wire in the chassis, as it’s really not necessary. We can’t pass modern safety regulations using cloth wire, so we got the next best thing. I’d also like to mention that, while we build higher quantities of hand-wired amps than all the other boutique builders, it’s still a very small number compared with the number of PCB amps we build, like our Hot Rod series and all the sold-state models. Our factory estimates about eight times the labor in a Vibro-King versus a ’65 reissue amp with a PCB.

TQR:We would assume that Fender has a separate group of employees devoted to building the hand-wired amps.

Shane: We do have the hand-wired team in a separate area in the factory. They are highly trained, patient employees who take a lot of care with these amps. Most of them are women, same as Leo’s day, maybe because they tend to be more patient than us dudes. And women’s hands tend to be smaller, making it easier for them to run wires and solder connections in the tight confines of the amp chassis. I don’t know the training regimen off hand, but I believe many of them cut their teeth on guitar wiring before moving on to amplifiers.

TQR: With the tweed Deluxe in production, are there plans to develop additional hand-wired Fender models of the past?

Shane:Yes. The list of great old Fender amps begging for reissue is a long one!

In case you don’t know, Mercury is known for having acquired and cloned hundreds of stellar vintage transformer sets that com-prise their ToneClone and Radiospares series…

TQR: How did you become involved with the development of the 5E3 specifically?

Sergio: It call came about as a follow up to the ’57Twin-Amp reissue project that we were a part of a few years ago. Mercury designed and supplied Fender with the transformers for those amplifiers, which was a very successful endeavor—so much so that Eric Clapton made them his main amps for his own tours and the Cream reunion tour.The momentum started by the ’57 Twin-Amp project quickly created a demand for some sort of follow-up amp in this positive vibe, and Fender’s decision to reissue the 5E3tweed Deluxe came as good news to us. It is probably the most copied circuit on the planet, and I couldn’t think of abetter project to sink our tranny designer teeth into.

Years ago the late Ken Fischer, of Trainwreck, told me that the Deluxe was an early inspiration for him to get into amp building. He went as far as to refer to the Deluxe circuit as the cornerstone of the boutique market. It’s a truly different dynamic when the company that started it all wants to reintroduce a benchmark in amplified guitar tone, and especially when their goal is to make the amp sound as fresh as it did when it was first launched. We’ve worked for decades acquiring our extensive library of transformer designs that originate from variants of pre-production to pilot runs of many vintage amps, so amplifier companies often consult with us because we’re a small but dedicated group just nutty enough to be the conservators of such things.


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