He came up with the preamp, tone, volume, balance, power amp designs 35 years ago. He's been forced to make minor component value changes as semiconductors came and went.

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The design is somewhat minimalist, the most innovative is his active bias scheme. I've never seen anything like it anywhere and trust me, while I am not an audiophile I do keep up with "State of the Art" designs as a hobby.

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I'm at a loss to understand how using one batch of transistors produces great sound, and yet another batch of the same transistors produces "muddy" sound.

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I have some nice audio programs, including some FFT with different display modes. Tomorrow we hit the amps, a good one and 'bad' one, with every trick in my inventory. I've borrowed a high end analog to digital converter that is flat +/- 2dB from DC to 1MHz. I'm hoping pink noise bursts show something.

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Jimmy started out as an architect but started his audio business because 'modern designs make me want to barf.' He hates parking lots that are laid out decoratively with all curves, tall bushes etc. He moved to England, was licensed and was increasingly depressed over the new buildings in London.?

"Nuke the city and start over."

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As children we'd play and combine our Lincoln Log sets (my father marked all of mine with a T his with a J_ and Jimmy build amazing tunnels for my Lionel electric trains. He built a model of Windsor Castle from sugar cubes in the 9th grade, won a design award.

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He is self taught but knows his semiconductor design tech better then any real engineer I know.

He is the only person I know who will tackle an failed switchmode power supply and has an almost 100% success rate for reliable repair. The few he gave up on he pointed out design flaws.

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