The Jim Kelley 2 Channel Line Amp  
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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