Burning Amplifier # 1 — Nelson Pass / 2009

The Burning Amp Festival is an event every October in San Francisco. Do-it-yourself audio enthusiasts from all over gather to show off their projects, listen to talks and equipment demos, and rub shoulders with the rich and famous. Having a very large collection of audio parts and diminishing storage space, I seem to have fallen into the role of Santa Claus there, distributing components and cheap advice, with white hair, beard and a large elf (Colin Pass) to add verisimilitude. This year we also brought a batch of unfinished amplifiers, consisting of a chassis, connectors, transformer, power supply capacitors and… More...

Single Ended Class A — Nelson Pass / 1995

Single-Ended Class A amplifiers have certainly hit it big in the four years since we began testing the first Aleph 0. So is this just another audio fad, or is there something fundamental about this kind of design, justifying a revival of the old approaches to amplification? When I started designing amplifiers twenty-five years ago, solid state amplifiers had just achieved a firm grasp on the market. Power and harmonic distortion numbers were the important thing, and the largest audio magazine said that amplifiers with the same specs sounded the same. We have heard Triodes, Pentodes, Bipolar, VFET, Mosfet, TFET… More...