About Pass DIY

Nelson Pass has been an early contributor to the audio DIY scene; It has been said that Nelson has a knack of explaining engineering things very clearly in a few words, and that he obviously enjoys doing it. He is also a very active contributor at www.diyaudio.com. Being very generous with advice, tips, and complete amplifier designs that people can build.

What does Nelson Pass get out of this interaction?

“I like to speak to the teenager (me) who wanted to know this stuff—that's my audience. There are always people who appreciate a decent explanation that gets to the meat and potatoes. I see it all as light entertainment with a little education thrown in. The academic paper approach has its place, but it seems intended for people who mostly understand the stuff already. If you want to communicate with DIYers, you depend more on colorful analogies, a little hand waving, and very little  differential calculus. I get lots of personal satisfaction out of the whole enterprise. It gives me an outlet for some cool ideas and things that otherwise would stay bottled up, and I have an excuse to explore offbeat approaches purely for their entertainment value. Also, the process of communicating DIY stuff is a two way street—I would say I get about as much as I give. Nelson Pass”

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...

Power Supplies — Nelson Pass / 2001

Lots of people don't understand electricity, but they do understand plumbing. Hydraulics provides a good analogy in understanding basic electrical flow. Wire is a pipe. Water pressure is voltage. Water flow is electrical current. Lakes and storage tanks are capacitors. Diodes are one-way valves. Tubes and transistors are faucets. The entire power circuitry of an amplifier can be seen as a community water system. The sun, driving the weather cycle, deposits water on the landscape, and it collects in a lake behind a dam. The community draws water as needed through pipes. In the winter, the rain collects in the… More...

Zen Variations 7 — Nelson Pass / 2004

One of the performance issues raised by the original Son of Zen (Audio Electronics, #2, 1997) was its efficiency figure, which was charitably described as 4% (500 watts in, 20 watts out). You may recall that this was dictated by the original requirements - no feedback, no capacitors in the signal path, and a single gain stage. Zen Variation 6 relaxed the requirements on feedback and capacitors in order to provide a tutorial exercise about “super-symmetric” feedback. The performance was improved in distortion and output impedance, but the efficiency was only slightly improved, largely because we used most of the… More...

Copyright © 2016 Pass Laboratories, Inc. All rights reserved

Telephone: 530.878.5350