New Stasis front end

I particularly like the sentence in the attached manual which reads: "Assembly and final adjustment is completed under the supervision of Nelson Pass, originator of the Stasis circuit and co-founder of Threshold"

So maybe if Nelson reads your post, he might be able to shed some light on your question. :wiz:

That is the hope. This thread is quite interesting and informative. The pcb posted in #1 could be used as a preamp or a headphone amp. Just short the bias spreader.
 
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Here's a simulation of the complete amp with 2 output devices: 0.0026% THD at 1W out.
You may want to put the .asy file in the symbol directory of your LTspice installation.
 

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Just re-read whole thread once again. Great job!

Would also be very interested in duplicating Threshold SA1 monoblocks with new FE.

I have Thiel CS6 that are very amper hungry. I’m not afraid of huge heatsinks, large toroids and many output pairs. Just would like to make it once and good :):):) preferable as mono amps. Any help how output stage would look and how many output devices to use?

Many Thanks!
 
THRESHOLD's Excellence

dunno which models, but details lies in these text parts:

"common point for parallel mono amps"

"output + binding post except inverting channel of bridged amps, in which case connection is made to - binding post"

"NOTE 2. ..................... and 1/2 of the complete output stage for mono amps"

conclusion - Lego blocks are here ....... you can combine 'till the end of time :)

fact - I'm utterly lost in Treshold models nomenclature ....... stopped even trying to figure it out

Hello Zen Mod and all,

The renaissance of STASIS [R] in this thread is a testament to its 'foreverness'.

I attached a beautiful art picture to complement your schematic. It was shown in AUDIO November 1991.

Best
Anton
 

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Official Court Jester
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of course - you need two OS pcbs when going SUSY, to have first and second to make bridge of them

with 40V rails, let's say round figure of 35V is what you get after losses at peak, so voltage envelope is 70Vpp

that's what you get from one half of bridge

other half of bridge is driven in opposite phase, you have another/once more 70V in opposite phase, so in bridge that's 140Vpp

140Vpp/2/1.41 gives you 49.5Vrms

as P= Vrms^2/Rload, that's 306W @ 8R

heat is in direct relation with how much of that you want to be in A Class, dictated by sheer size of your enclosure ( say 55C in Summer) and greenies you invest in PSU

for that , I wouldn't go with less than 99mF per rail ........ and nice 800VA Donut ....... speaking of one channel

though, do not forget that SUSY part of project isn't verified in vivo - most likely it needs some polishing, to get desired level of stability, mainly thinking of absolute and relative offsets

Mighty Moi is not going that route, too much on my plate already
 
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of course - you need two OS pcbs when going SUSY, to have first and second to make bridge of them

with 40V rails, let's say round figure of 35V is what you get after losses at peak, so voltage envelope is 70Vpp

that's what you get from one half of bridge

other half of bridge is driven in opposite phase, you have another/once more 70V in opposite phase, so in bridge that's 140Vpp

140Vpp/2/1.41 gives you 49.5Vrms

as P= Vrms^2/Rload, that's 306W @ 8R

heat is in direct relation with how much of that you want to be in A Class, dictated by sheer size of your enclosure ( say 55C in Summer) and greenies you invest in PSU

for that , I wouldn't go with less than 99mF per rail ........ and nice 800VA Donut ....... speaking of one channel

though, do not forget that SUSY part of project isn't verified in vivo - most likely it needs some polishing, to get desired level of stability, mainly thinking of absolute and relative offsets

Mighty Moi is not going that route, too much on my plate already

Oh yes, I see where I stuffed up. Have to go with lower voltage rails then.
Thanks Zen Mod!