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”

Zen Variations 8 — Nelson Pass / 2005

Thanks to a nice person on the Pass Labs Forum ( www.diyaudio.com ), I became aware that high current power JFET transistors are again available. You can check them out at www.lovoltech.com which offers a small variety of high current N-channel vertical JFETs in TO-251 and TO-252 packages. They don’t hold a lot of voltage 20-24 volts) or dissipate lot of power (69 watts, derated at 1.8 watts/degree), but they do deliver up to 100 amps peak. Clearly designed as switches, they nevertheless offer a linear operating region and are attractive for audio amplifier design. Small signal JFETs are routinely… More...

The Sweet Spot — Nelson Pass / 2009

Every audiophile understands the concept of the “sweet spot”, that happy balance of conditions that elicits the best possible sound. It can be a particular listening spot, the best positioning of loudspeakers, or the fortuitous combination of components which complement each other perfectly. It should be no surprise that the desire for the best performance takes the search for the sweet spot into the interiors of the components themselves. This article will concern itself with finding the sweet spot for each gain device in audio amplifiers. It is a commonly held belief in audio that the best amplifiers are composed… More...

Zen Variations 9 — Nelson Pass / 2006

In ZV8 we dipped our toes into the waters of power JFET transistors using the new Lovoltech LU1014D in a simple circuit. The focus of the project was on the JFET itself, and except for a cascode transistor the rest of the amplifier used only passive components. Here in four installments we will increase the complexity of the circuitry around the JFET with an eye toward distortion performance surpassing any of the Zen projects to date. Much of this project will make reference to ZV8 (AudioXpress, January 2006 and www.passdiy.com), which discusses the characteristics of the LU1014D power JFET and… More...

Copyright © 2016 Pass Laboratories, Inc. All rights reserved

Telephone: 530.878.5350