Search Results for: Tweed Champ


Tweed Champ I

Amp Transformers, Output Transformers & Chokes

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.

 

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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Crimsontone SE Mini Amp Review

Decades ago, practice amps were effectively no-frills versions of their bigger brothers. Even so, those little amps of yesteryear became something magical in the studio. From Jimmy Page and his Supro to Joe Walsh and his Fender Champ, getting big sounds from little amps became the stuff of legend and a go-to approach for recording. Crimsontone Amplifiers embraces this philosophy in a big way—only two of the seven amps the company offers are 20 watts or more. Their newest amp—the 4-watt SE Mini—is a testament to the power of small and a cool nod to the role of low-wattage amps in the history of rock ’n’ roll.

In the Court of the Crimson
At just 7.5 pounds, the SE Mini certainly lives up to its name. The cabinet is covered in a tough red tweed fabric, and it features a sporty aluminum handle for easy transporting to the studio—or a gig in the park for that matter. Crimsontone didn’t design the SE Mini with gimmicks in mind either, which is evident in the simple feature set. It has just four controls—Gain, Tone, and Master knobs, along with a tiny Gain Boost switch.

The single-ended, all-tube head is powered by a Sovtek EL84 coupled to a JJ ECC803 preamp tube and a Mercury Magnetics GA5-P power transformer for a maximum of four watts. The GA5-P is part of Mercury Magnetics’ fantastic Toneclone Plus line, which is stocked with the company’s replicas of famous power transformers from the past. In this case, it’s a faithful reproduction of the transformer in Gibson’s 1950s Les Paul Jr. combos. I was pleased to see that the output transformer was also a Mercury Magnetics model, an FTCO-M that replicates the units in Fender’s Tweed Champ amplifiers of yore.

The SE Mini doesn’t rely on modern circuit design, but instead forgoes current technologies for a traditional, handwired, point-to-point circuit. Upon pulling out the adorably small chassis, I was treated to the sight of tidy wiring held together with clean solder joints and tight mounting. And the Components—F&T filter caps, Alpha pots, Orange Drop capacitors, carbon-comp resistors, two Xicon power resistors, and a Cliff input jack—are all top-of-the-line.

Good Things … Small Packages
Crimsontone touts the SE Mini as a practice amplifier, but it excels at hitting tones in the ’60s classic-rock vein. With a Fender 60th Anniversary Telecaster and a feed to the two 12″ speakers in a Fender Twin Reverb reissue, the Crimsontone’s clean mode belted out seriously raw, garage-rhythm jangle with a dash of classic Neil Young sting thrown in. The highs are crisp and brash, with tight lows and a gritty midrange. With a Gibson Les Paul Studio, the amp accentuated the midrange and softened highs, but the amp still retained its bold essence, staying tight in the low end and having a nice, even sag. It’s not a sound for everybody, but it speaks in the raw, unadulterated tones of no-holds-barred slingers of the first classic heavy rock era.

It’s worth noting that, while the SE Mini kicks with James Gang-worthy tones, I did have to really work with my picking hand to squeeze any real dynamics out of it. That said, that’s not uncommon with most small-wattage amps, and it certainly doesn’t mean that the amp isn’t touch sensitive. But if you’re used to using a big Marshall to get your ’70s tones, the SE Mini will feel like an entirely different animal. The amp doesn’t have excessive gain or saturation to hide behind, so it assures that you hear every single mistake. The sweet sounds that come as a trade-off are well worth it, though.

This Dog Bites
Getting the most meat and bite out of the SE Mini requires careful adjustment of the Gain and Master knobs. With the Gain Boost switch off, not much grit is available from the Gain control. Rather, it acted more like a voicing control, altering the feeling and response of the tone. Most master-volume tube amps have a gain structure that changes from tighter and crisper to warmer and spongier as you increase the Gain. Without the boost on, the Gain control on the SE Mini reacts the same way, but without adding huge amounts of saturation. Kicking in the Gain Boost adds a dose of rage to the tone, and I thoroughly enjoyed playing quick double-stops and soaring country bends with the SE Mini’s overdrive-infused, high-midrange snap.

Predictably, the boost kicks up the volume a few decibels, too. And I discovered by lowering my guitar’s Volume knob just how well the amp cleans up at even the dirtiest settings. The Gain Boost adds noticeable touch sensitivity, too. I got one of my favorite tones by dropping the Telecaster’s Volume down a quarter of the way and letting my picking-hand attack determine the amount of overdrive.

If you’re looking for more aggressive tones, it also pays to keep the Master at or near its highest levels. At practice-amp volume levels, the Telecaster sounded a little thin, and understandably so—I wasn’t pushing the single EL84 enough until I moved the Master to 3 o’clock, where there was a considerable volume jump. The sweet spot on the SE Mini’s Master is just a little higher, where it retains just the right amount of definition, while maintaining ample punch. Set the Master there and use the Gain control to set the flavor of the attack, and you’ll find a load of tone variation at your fingertips. Working within this range helped me keep the Tele’s bite under control and let the raw nature of the amp’s voicing shine through.

The Verdict
Four watts may not be the right recipe for tearing the paint off walls, but the SE Mini uses a well-designed circuit and quality components to sound much bigger than it looks— especially with a few 12″ speakers at the receiving end of its signal. Crimsontone’s SE Mini is a great choice for lovers of dirty, jangly rock guitar tones. But, like tube practice amps of yesteryear that needed to be driven and played hard to achieve their fullest tonal potential, it can require a more dynamic and forceful touch to tap into its inherent dynamics. Still, there’s nothing quite like a healthy, low-watt tube amp cranked to high heaven for creating sweet, raw, rowdy sounds. In that musical category, the SE Mini is a hit.

Buy if…
you’re a fan of dirty, to-the-point guitar tones at reasonable volumes.
Skip if…
you need to be heard over a drummer or can’t abide bone-simple feature sets.
Rating…

Street $799 – Crimsontone Amplifiers – crimsontone.com

Source: https://www.premierguitar.com/articles/Crimsontone_SE_Mini_Amp_Review

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

FTC

4H / 500mA Choke — Fender Tweed era Part # 14684 — 3 1/8″ center to center

*This choke is for Tweed era amps such as Bassman & Low Power Twin (not a Champ!)

FTCC

Tweed — 5E1 — 5 Henry, 370 Ω DC resistance, 40 mA current rating

2″ center to center mounting holes — same as Tweed Princeton choke

FTCP-59-CT

59 Tweed — 330-0-330 — Center Tapped Filament Wind — 5V winding

FTCP-59-100

Tweed — 100V & 120V primary

FTCP-6

Mid ’50s Tweed — 260-0-260 — CT on the 6.3V winding — 5V winding

FTW-CHMP-OM

Tweed — single 4 Ohm tap — oversized

FTW-CHMP-OS

Tweed — single 8 Ohm tap — oversized

Mercury Magnetics Trannies and Choke

Many of you are already familiar with our resident amp tech, studio owner/engineer and advisory board member Jeff Bakos. In his spare time, Jeff occasionally builds amps for clients on request, and lately he’s been asked to build… you guessed it – small little biters. Since his personal GA-5 has been featured so often on various recording projects, Jeff toyed with the idea of recreating the Gibson GA-5 Skylark for a minute, but given the fact that vintage GA-5s remain fairly plentiful, he ultimately decided to design his own simple take on a smallish amp – the 8 Ball. Housed in a Mojo Champ cabinet, the 8 Ball is built with one of our favorite tens, the Eminence Legend Alnico 1058 (that’s a hint), Mercury Magnetics trannies and choke, and premium components, including Sozo coupling caps. With the bigger Mercury Princeton transformer set, the single 6V6 / 12AX7 / 5Y3 design is capable of producing 10 watts of power. Features include dual inputs, volume and tone controls, a front panel line out jack, and a “vintage” / ”modern” toggle switch also conveniently mounted on the front panel.

The “vintage” setting produces pristine Fendery clean tones up to 12 o’clock on the volume control, gradually followed by a progressively thicker growl with intense distortion and sustain. In this setting, the 8 Ball surpasses all the other small amps we’ve reviewed in terms of practical versatility with stronger, louder clean tones and a more gradual It’s back! We are now resuming limited production of our meticulous recreation of the original 1959 DeArmond R15 1×12 amp. You may recall that we initially produced a limited number of TQ Clarksdale amps in 2006, before our supplier for the original chassis informed us that small runs would no longer be possible. We’ve found a new supplier, and the TQ Clarksdale “DeArmonds” will be built again by Jeff Bakos with our original specs – pin cabinet construction and design identical to the original, original Mercury Magnetics Tone Clone transformer set cloned from our original ’59 DeArmond, hand-wired chassis, premium components including Sozo caps, Celestion G12H 70th Anniversary speaker, premium JJ and Tung-Sol tubes, Evidence Audio speaker cable, custom gold grill cloth and blonde Tolex covering. This 22 watt design represents one of the rarest and most toneful combos ever built. The original 1959 DeArmond 1x12s were built for just one year in Toledo, OH, and a clean example recently sold on eBay for $7000. In 2006 Jeff Bakos meticulously blue-printed our original DeArmond, Mojo created CAD drawings from the original cabinet design, and we sent the transformers to Mercury Magnetics to be cloned. The result is a phenomenal 1×12 that will generally kick any tweed Deluxe straight to the curb with a bigger, bolder voice and lush, musical distortion cranked. The 4-input, cathode-biased Clarksdale can be operated with dual 6V6s and 5Y3 rectifier for optimum burn, or a pair of 6L6s and 5AR4 for slightly more power and clean headroom. Blonde Tolex only, simply because it’s the coolest color…

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Amp Transformers, Output Transformers & Chokes

FTCP-59-240

’59 Tweed — 220V, 230V & 240V primary

FTCHMP-O

Mid ’50s Tweed — single 8Ω tap — 2″ mounting center

FTCHO-4

Mid ’50s Tweed — single 4Ω tap — 2″ mounting center — medium size version

FTCHO-5

Late ’50s Tweed — single 4Ω tap — 2-3/8″ mounting center — largest version

FTCHO-5M

Tweed — 8Ω tap

FTCO-6

Early ’50s Tweed — single 4Ω tap — 1-3/4″ mounting center — smallest version

FTCO-M

Tweed — 4, 8 & 16Ω taps

FTCP-59

59 Tweed — 330-0-330 — NO CT on the 6.3V winding — 5V winding

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