A Concise Guide to the Published Amplifier Circuits of Nelson Pass

Thanks to answers elsewhere in this forum, I have added a section on current source amplifiers titled Current Output Stages.

P.S. I sort of painted myself into a corner by publishing a URL with the word "draft" in the title. Now I can't drop the _draft without risking folks finding a dead URL or an outdated file. Oh well, I guess this will forever be a draft document.
We have the original list in post 1.
Can we have a regularly updated list 2 for all the other links that are turning up?
So far, I am only aware of the BA-3 article, and it is not available as a PDF. I also have not really noticed any new articles that have been officially listed on the Pass Laboratories, First Watt, or Pass DIY sites.

Once new articles appear there, it is my intention to update my Guide by categorizing them.

I also welcome suggestions on how to handle revisions. After I published a URL with guide_draft.pdf as the file name, I realized that I could not rename the file easily without stranding folks who had only the old URL. So far, that's not been a problem, because I have simply updated the guide_draft.pdf file several times since initially publishing it. There's not really much new information, just refinements and small additions. But, if I were to incorporate entirely new articles then I think I'd have to do something more. I suppose that I could create a cover page in HTML that lists revisions, but perhaps there's a better idea.

Nelson Pass

The one and only
Paid Member
2001-03-29 12:38 am
Existing articles are scheduled for updating on the sites.

The (big) SIT article is scheduled for then next Linear Audio, unless I am mistaken.

The (small) SIT is on the FW site now.

The Beast With a Thousand Jfets is about done. I just have to figure where
to send it.

The F6 amplifier is done, but the article text has not been written.

Six other titles are nominally in the queue, but giving away the titles would
be telling...

Occam's Razor for every Greedy Boy ......

is F6 best ever , 42 of all amps ........... or that will be object of some of future 6 articles ....... and how many times we'll have 6 articles more , after these 6 .... ???!!


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2011-04-29 8:37 pm
I have read all of the articles by Nelson Pass, and then went back and tried to take notes on what topics were discussed in each. Here in the Pass forum, a few folks (myself included) are new, and hoping to find a decent starting point. For my part, I have compiled an index of the articles that I think are necessary for understanding the Pass amplifiers, including Zen Variations and First Watt.

The linked file is a first draft. If anyone has suggestions, please let me know. As I learn more, I hope to flesh out the guide and then make a final version before too long. At the moment, 4 pages (with two focused on the juicy bits) seems like a good length. I've included some very basic comments about some of the technology, but perhaps I could revise this to be more of an introductory tutorial which points to Papa's more in-depth coverage.

A Concise Guide to the Published Amplifier Circuits of Nelson Pass

Brian Willoughby

This link is bad.