Burning Amplifier # 2 — Nelson Pass / 2009

In Burning Amp 1 we examined an amplifier circuit designed to complement the hardware we gave away to some attendees at last October's Burning Amp Festival in the San Francisco bay area. This first design centered on a power output stage having of four banks of parallel N channel Mosfets. It was a single-ended Class A amplifier which delivered high quality sound with only local feedback. Burning Amp 2 will use virtually the same front end and power supply but coupled to complementary banks of N and P channel power Mosfets used as followers in a push-pull Class A configuration.… More...

The Pass A-40 Power Amplifier — Nelson Pass / 2000

FLATTERED BY THE opportunity to publish a project circuit, the designer is often beset by seemingly contradictory considerations. On the one hand, it is tempting to design a complex circuit as a demonstration of technical prowess; an amplifier with large numbers of esoteric components performing obscure functions. Such an amplifier might be a smorgasbord of electronic technique, featuring class A operation, cascoding, constant current sources, current mirrors, and extra-loop error correction. It would be fascinating to build and perhaps would also sound good. On the other hand, complexity is not a good end in itself and a much simpler circuit… More...