Papa's original Stasis FE pcb, with few more holes for standoffs
see graphical files
enclosed zip - all of those, plus Gerber files in separate folder
see graphical files
enclosed zip - all of those, plus Gerber files in separate folder
Attachments
Well Zen Mod, you have outdone yourself again and thanks to Nelson for reviving this classic design and to both of you for following through on it - we all have a great Christmas present.
Once again, from all of us around here a very big thank you, to both the resident amp guru's.
Once again, from all of us around here a very big thank you, to both the resident amp guru's.
One other quick question ZM, what are the pcb dimensions of the NP FE board you added the 2 extra mounting holes to. It looks like you might have increased the size on one of the dimensions from the original 5.5" x 3.5" (139.7mm x 88.9mm)
Thank You Zen Mod for the hard work! And once again a tremendous thank you to Nelson Pass for giving all of us another amazing amp to build and enjoy 
Stasis 2020...(nearly) the only good thing to come from 2020?
This is exciting. Big thanks to Mr. Pass and ZM. I haven't heard a ton of systems, but I heard a Threshold Stasis (forget which model) driving a pair of Thiels a couple years ago...and it was one of the best systems I've heard so far.
I have yet to build my first DIY Pass amp, but I have built several headphone amps including the ACP+ and a couple Millett Maxes, and also a Mauro Penesa MyRef Rev C, all with little if any trouble (thanks to all the excellent documentation on those projects). I was strongly considering starting my Pass DIY journey with a MoFo or Aleph J, but now this modern Stasis has caught my eye, and so have the teases of the new Sony VFET amp.
Thoughts or recommendations?
Also, does anyone have background info / specs on this? I.E. something similar to the specs that Pa has for his FW amps here FIRST WATT PRODUCTS
This is exciting. Big thanks to Mr. Pass and ZM. I haven't heard a ton of systems, but I heard a Threshold Stasis (forget which model) driving a pair of Thiels a couple years ago...and it was one of the best systems I've heard so far.
I have yet to build my first DIY Pass amp, but I have built several headphone amps including the ACP+ and a couple Millett Maxes, and also a Mauro Penesa MyRef Rev C, all with little if any trouble (thanks to all the excellent documentation on those projects). I was strongly considering starting my Pass DIY journey with a MoFo or Aleph J, but now this modern Stasis has caught my eye, and so have the teases of the new Sony VFET amp.
Thoughts or recommendations?
Also, does anyone have background info / specs on this? I.E. something similar to the specs that Pa has for his FW amps here FIRST WATT PRODUCTS
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ZM sorry to ask a dumb question, but I am confused by original and ZM version, can you give me the cliffhanger notes on the differences please, I see some values are different but where would I use which one?
just bid your time, grasp several possible iterations in future (rails, Iq), then make your choice
(partly) contrary to story I was selling on start of thread, no amp is too complicated for build even for novice, under condition that you use build as frame for learning how to do things methodically and with care, asking for explanation and guidance whenever you need
build whatever you wanted previously ....... and build Stasis, too 🙂
"resisted Babelfishing urge, added one cap and few base/gate resistors"
Absolutely incredible!
Thank you to Nelson, to Zen Mod, and to anyone else that contributed toward bringing this gift forward to the community.
Thank you to Nelson, to Zen Mod, and to anyone else that contributed toward bringing this gift forward to the community.
Absolutely incredible!
Thank you to Nelson, to Zen Mod, and to anyone else that contributed toward bringing this gift forward to the community.
I second that motion! Amazing generosty of NP, great design work and contributions from ZM, 6L6, PicoDumbs, GaryS and everyone else involved.
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This might be a fine substitute front end for the A75. +/- regulated 50 volts and a bunch of mosfets for the output stage?
BDP
BDP
if you have functional A75, do not
it is a Jewel per se, damn fine amp
besides, article being a Goldmine of tricks, both practical and conceptual
I'm still reading it from time to time, same as favorite book - I know everything, but each time I'm finding new things to enjoy ...... why somewhere one comma is omited, why somewhere one is too much .......
serious work, Man.....
A few of my thoughts were:
1. No dual differentials. Norm Thagard commented in the article.
"Although Nelson is no advocate of dual differential designs, he left that
part of the original proposal undisturbed".
2. Wouldn't have a balanced input impedance that is less than 600 ohms, might be beneficial depending on your source.
3. Direct board swap and wouldn't have to cannibalize the existing case or front end.
Plus,
Its getting up there in years (20+) and should probably start thinking about changing out the capacitors.
I'm going to stop posting now, I'm reminded of how old I'm getting 😱
1. No dual differentials. Norm Thagard commented in the article.
"Although Nelson is no advocate of dual differential designs, he left that
part of the original proposal undisturbed".
2. Wouldn't have a balanced input impedance that is less than 600 ohms, might be beneficial depending on your source.
3. Direct board swap and wouldn't have to cannibalize the existing case or front end.
Plus,
Its getting up there in years (20+) and should probably start thinking about changing out the capacitors.
I'm going to stop posting now, I'm reminded of how old I'm getting 😱
Attachments
if that is made inside as you did it outside, it'll be pity to touch it, except recapping ......
1. from that time, Nelson certainly learned to love them all, while knowing how to tweak for taste 🙂
2. my sources are happy even low down
3.well, I'm just chatting, of course that choice is only yours; though, for that, better wait for Papa's FE iteration for mosfet OS, as Jim mentioned in #116 ....
The A75 articles are the ones I refer back to more than any other. I was actually reading part 2 earlier today. “Goldmine” is a perfect description.
From time to time someone asks Nelson for a ‘larger’ amplifier. A balanced A75 would fill the bill.
Graeme