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...

Zen Amplifier Revisited — Nelson Pass / 1994

I must say that I have been very gratified by the response to the Zen amplifier from the last issue of TM. Since writing the article I have had an opportunity?to build another 25 copies of the amplifier, listen to it on a larger variety of loudspeakers, absorb criticism from the readership, and generally meditate on the project. Areas of criticism of the design all relate to the objective, measurable performance, but in addressing them, I found that the subjective performance improved with the measurements. All of the changes are performed without altering the original topology of the project amplifier.… More...