The Jim Kelley 2 Channel Line Amp

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The Jim Kelley Power Attenuator

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  In 1978 I quit my band, sold my Alembic bass, rented shop space from luthier Dale Fortune, and began doing business as Active Guitar Electronics in Tustin, Califonia. Relying on my college electronics degree, years as a TV broadcast engineer, and my experience working for Forrest White, Tommy Walker and Leo Fender at Music Man in Anaheim, I went to work doing amplifier repairs and modifications. As a result of this work, I determined that the push-pull output section of an amplifier produced a better sounding distortion than did the preamp section in master volume type amplifiers. It seems obvious now, but at the time it was a profound revelation. Subsequently, I built a series of prototype amplifiers, and with the tireless help of Todd Wilson from Fortune Guitars, I endeavored to eliminate any and every detectable bad sound from the amp. This resulted in a final design which I showed at the 1979 Winter NAMM under the Fortune name. The basic amplifier had 6 tubes and 3 knobs. It was an electronic hot rod, and it was small and loud. I sent one of those first 5 prototypes in a figured mahogany cabinet to Eric Clapton out of gratitude for the profound effect his music had on my life.

  The amp was loud, and so to solve the volume control problem, I devised a variable L-pad device capable of handling the high amount of power produced by the amplifier when driven to full power. This provides essentially the same function as a master volume, only the sound is much better. My Power Attenuator remains one of the best guitar amp attenuators ever devised.

  Thanks in part to Fred Walecki at Westwood Music, LA session and touring players began to hear about the amps. These included, among others, Carl Verheyen, Jake Hill, Mike Hamilton, Steve Farris, Richard Bredice, Bruce Boulanger, George Johnson, Curt Eilenberg, Robben Ford, Ricci Martin, Jim Messina, Dean Farley, Billy Hinsche, Carl Wilson, Dan Yablonka, Jerry Jeff Walker, Gary Puckett, Daryl Stuermer, Doug Freeman, Mark Kendrick, Lee Ritenour, Pat Hennessey, Randy Thomas, Dana Olsen, Alan Holdsworth, Prince Robinson, and Ray Parker Jr.

  Those are some of the people who I can recall using the amps and suggesting features such as reverb and channel switching (obviously I've forgotten the names of hundreds of others). By the end of 1979, the Reverb Model had become the mainstay of our amp line and I decided to market the amps under my own name. Initially, in order to answer the need for switching, I added a footswitch to the power attenuators. This allowed players to turn up the volume on their guitar for an overdriven solo tone with the attenuator engaged, or back-off the guitar volume and bypass the attenuator for a clean rhythm sound.

  It was around this time that my dad, Stan Kelley, introduced me to record producer Rob Fraboni. Fraboni, who worked out of Shangri La studio in Zuma Beach, apparently loved the amps and recommended them to seemingly everyone. Through Rob, we were introduced to a number of recording artists including Vince Gill, Jeff Wilson, Rick Beilke, Max Gronenthal, Johnny Lee Schell, and Bonnie Raitt - more than I can remember. The amps were used on a number of albums recorded at Shangri La. Rob Fraboni was probably the single greatest contributor to the success I have had in my amp building career.

  By the end of 1980 we had begun exporting amps to Japan (through Hank Hoshino), Germany (though Musik Jellinghaus), and Australia. Over the next few years we built an elite dealer network across the US. It was through our New York dealer, Rudy's Music Stop and John Suhr, that we were introduced to a number of prominent East Coast artists. Among them include Jack Sonni, Lou Reed, and Mark Knoffler (recording in New York at the time). In the modern day, players such as Joe Bonamassa and Pete Thorn, as well as European artist Ángel Miguel have become enthusiasts. There are undoubtedly others, but this is the best of my knowledge and recollection.

  The FACS (foot activated channel switching) amp was the result of an epiphany. For weeks I had been considering all the various possibilities and problems associated with a channel switching amp. The main problem to solve was what features to provide, and more importantly how best to incorporate them without sacrificing tone. The amp needed to be a true advancement, not just a repackaged revision with new doo-dads. For me there is beauty in simplicity, so I sought a simple solution. I knew that the JK tone controls worked great for clean rhythm, and for blasting overdrive, and that each use had unique settings. And I knew that I needed to incorporate the power attenuator into the equation, too. Then came the epiphany. It was in one of those rare moments of absolute clarity that I knew I should include two independent JK preamps, each with its own tone stack. In this way, optimal lead and rhythm eq's could be adjusted independently. And the preamps would be switchable as channel 1 and channel 2. I would also provide a separate reverb control for each channel. As the final piece of the puzzle, there would be an additional relay to simultaneously switch the attenuator. That was the genesis of the FACS amplifier.

  I learned early on that unmatched output tubes would distort asymmetrically, and produce notes that lack definition and sustain. And so from almost the beginning, I used matched output sets. But as a consequence, the resulting matched sets would require significantly different bias settings from one to the next. Back then, not everyone had the luxury of a personal amp technician, and I was concerned that the average guy might have difficulty correctly adjusting the bias when he replaced output tubes. It was for that reason that I began installing the LED bias indicator boards. It was a simple idea, based on the same measurement I used to match tubes. The circuit, as implemented, proved to be a bit too delicate in such an environment. But I think it was a good idea in principle.

  During the early 1980's, players began assembling refrigerator sized racks of equipment as part of their guitar rigs. During this period I was commissioned on a few occasions to build a rack mount preamp. I usually opted to stick pretty close to my standard circuit arrangement. This was fine as long as the customer wanted simply to obtain a clean signal from it. However I began to get requests for an overdrive capability, and this raised the specter of the dreaded 'master volume'. However, sticking to my ideals I resisted, and instead endeavored to create a Jim Kelley amp in miniature - at preamp level, complete with phase splitter, push-pull output, and a line level output transformer.

  The preamp must have worked well enough because I decided to incorporate the idea into a new version of FACS amp I called the Line Amp. For this amp I devised a new tone control that became saddled with the inglorious misnomer 'Pre-EQ'. In production it in fact became a passive, infinitely variable, post distortion, LC mid-boost and cut EQ control. As far as I know, it was the first of it's kind.

  By 1984, interest rates had sky rocketed and the dollar became expensive on the foreign exchange. Sales lagged and our exports all but ceased. Tom Sholtz from Boston was making solid state headphone amplifiers that sounded like a dimed Marshall stack, and American made tubes were fast becoming a thing of the past. Textbooks claimed that Field Effect Transistors produced transfer characteristics much like a pentode vacuum tube. And by this time I had determined that the circuitry surrounding the active elements contributed perhaps even more to the sound than the tubes and transistors themselves. So it was in this environment that I decided to experiment with an all FET amplifier. Although the experiment was a success, and the sound the amp produced was exceptional, there was at that time even less interest in a transistor amp than there was in my tube amps.

  In mid 1985 I hired an auction company to liquidate the company inventory and equipment. For six years we managed to build an average of 100 amps per year. In the beginning I was ambitious and intensely motivated to make the best sounding, best built guitar amplifiers. In doing so, I hoped that I might attain a good reputation. From that I naively expected success to inevitably follow. But it was the enjoyment of the work and the technical successes that provided me with my motivation. Eventually, for various reasons, the enjoyment subsided and it became time to quit.

  I want to thank all of my customers, employees and family, dealers, representatives, and artists who believed in the amps and supported us back then. It was you who gave a voice to the amps, and helped build a legacy. Carl - I'll always regret not coming to that show, and Vince, you were the nicest of all. To all, and especially to those I have forgotten to mention, thank you with all my heart.

  Jim Kelley  

  "500,000 halos outshined the mud and history. We washed and drank in God's tears of joy. And for once, and for everyone, the truth was not still a mystery."

 Jimi Hendrix

 

Inquiries:    jimkelleyamps@gmail.com

Thanks to Ryan Reschan and Matt 'Max Harmony' Harmon for their help assembling this website

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