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Kevin Beller

// The Designer



I was part of the team that designed the original 100 Watt Convertible. It included Roger Modjeski and Bruce Kennedy, both from Harold Beveridge, a manufacturer of ultra-high-end hi-fi equipment. Roger went on to start Music Reference, a manufacturer of vacuum tube hi-fi products and RAM Labs a supplier of computer graded and matched vacuum tubes. The Convertible was a very unique design and quite advanced for the time. We were one of the first to employ an ultra-linear output stage with a variable damping control and triode/pentode switching. We were awarded two patents, one for the user assignable modular preamp concept that we used and another for our unique method of producing a variable power output stage. 17 years later when the patents expired, the idea was still fresh enough that at least one company copied the concept.


We went on to design a complete product line of amplifiers. This included a 60 watt modular amplifier, a 400 watt mono bass amp and a 400 X 2 bi-amplified bass amp. We also designed second generation models of all of these in which we improved packaging and reliability. I personally designed two complete lines of speaker cabinets for both bass and guitar. Later, working with one other engineer, I designed a rack mount series of products that included a two channel vacuum tube preamp, a two rack space 100 watt/channel power amp (to my knowledge, the only one ever) and a single rack space 100 watt/channel class A solid state power amp. A few years later, I designed the 8440 and 8450; two vacuum tube combos using EL 84 tubes.



Over the years, I have grown to really love having animals around me as much of the time as possible. I currently have 7 cats and one three legged Malti-Poo, all of them rescues. They all have their own unique personalities and often, some very human characteristics. I have a personal relationship with each one of them and have found animals to be much more intelligent than most people give them credit for. They are also very adept at sensing your mood and know when to give you special attention.


My current favorite is a 5 string Bass guitar built by Fodera with pickups I designed and built in our custom shop. But I have several other instruments that have endured over the years.
The first instrument that I acquired and really liked was a ’68 Fender J-Bass. I had only played an old Gibson EBO before this point and was never satisfied with it. I was playing in an original band and the guitarist had a bass playing friend that was selling all of his possessions and moving to India (to find himself, presumably). He wanted $100 for the bass and a small practice amp. This was at the limit of my budget at the time, but I fell in love with the bass. It sounded so much better than my EBO and balanced well to boot. I eventually converted it to a fretless because the neck was like a roller coaster. I still have it 40 years later.


The next instrument is the one that became my long time workhorse. Back in the early days when we shared a building with Phil Kubicki, I used to go over and visit him on my lunch break. The first time, I noticed a Jazz bass blank on a shelf that had not yet been routed for pickups or a neck slot. A few visits later, I asked Phil about it. He said it was a reject he picked out of the trash when he used to work at Fender. I eventually convinced him to sell it to me for $25 and a great figured maple and ebony neck to go with it for another $125. I routed the body for a P-J setup, borrowed Seymour’s spray gun to paint it, bought hardware and assembled and set up the bass. This instrument became my main workhorse bass over the next 35 years, playing countless gigs, recording sessions and serving as a test bass for nearly all of the 4 string P and J-Bass pickups in the SD line-up. It got so much use, at one point I had to tear it down, rebuild the top surface where the control cavity had broken through from hundreds of pickup changes, and have the bass repainted. I had worn or chipped most of the original paint off. I still have this bass today. (Pictured under #3)



The Pickup Booster was the first pedal we ever produced. We came out with it back in the ‘90s at a time when no one was really offering a clean boost. The pedal was unique in many ways. It was the first pedal that was designed to interact directly with your pickup. It had a three-way resonance switch that allowed the player to significantly alter the basic sound of their pickups by changing the resonant frequency. This concept actually originated with some active bass pickups that we designed back in the mid ‘80s that had three miniature switches accessible from the top of the pickup. The Pickup Booster was also one of the first pedals to offer discrete, class-A circuitry with exceptional noise performance. We still offer this product in our current line of pedals; retaining the discrete circuitry, improving on the noise performance and adding a push-pull output stage for lower impedance and more output drive.


At the heart of any great product is a great PCB layout. We cut our teeth laying out PCBs for high voltage, high impedance and extremely high gain amplifiers and preamps. Any mistakes at this level are multiplied many times over and can easily convert your carefully designed and voiced circuit to worthless junk. It is impossible to have optimal noise performance and circuit stability if the board layout is not executed perfectly. We have spent decades refining grounding and signal routing technique and optimizing power routing for the lowest possible noise levels. Today we are pushing the envelope in packing the most features and performance into small packages, while advancing our standards for low noise and absolute stability.
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