My Stasis 3 runs cold

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My vintage Threshold Stasis 3 runs cold. I understand that this is a known issue with this design. I have seen references to a revised bias circuit. Anyone have experience with this? Anyone have details or a schematic for this modification?
 
The bias circuit in the amplifier has an adjustment pot which was designed so
that wiper failure puts the bias low. (Don't laugh, I have seen a lot of
examples where failure throws the bias high) :redhot:.

However, it is very unlikely that both channels would do that. More likely is
that someone adjusted the channels low.

😎
 
Left channel runs cold!

Hi. I have just received a pristine Stasis 3 - unopened! There is no sign of service or anything but dust down there... Outside is flawless!

But; the amp is running cold, very cold on left channel. Right channel became as hot as I can hardly notice with my hand.

* The amplifier is not much used regarding seller and with this temp conditions - is there necessary to change caps?

* Where is the voltage checkpoint for setting bias?

* The left channel is totally cold - is that the adjust pot or a dried cap around bias Components?

And a funny thing; I discovered a production fault; right channel input makes the left channel LED's to move.... and noone has been in there...... 😀

Greetings from Norway! :santa:
 
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Pristine Stasis 3

Pictures coming....
Starting with explaning last sentence..... my mistake.....
Not used to see right channel in the left side of amp 😉
 

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Some pictures of a pristine Stasis 3

Dark photos....
The amp beneath Stasis 3 is a DIY A40 - sounds wonderful!
 

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Biased amp today. 40,2 and 40,3gC with cover in place. 2mv dc right channel and 45mv dc left.

The amp sounds fantastic! Big crispy "want to play more" sound. Easy to listen to. I am a SET tube addict, but this amp do almost everything what SET do and is much better where SET is not so good. It has this tube-like sound in a good way.

This amp can play loud without pushing ears. It is easy to follow instruments and se instruments places i the sound picture. This transistor amp have the inne resolution known from Telefunken ECC803S. Some will know what I meen, an some do not have a clue...

This amp will stay! Feeding a pair of Tannoy studiomonitor with HPD 315A - and it is a match made in heaven!
 
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