Threshold S/500 bias set up anyone?

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Could use some more advise please!!

Hey everyone, while waiting on getting my new (to me) ML Ascents fixed, whole other story, anyway, I decided to go ahead and remove the "good" channel from my S-500 to remove and replace thermal compound between outputs and sinks. Much to my surprise when checking the outputs I found an "N" with a dead shorted EB junction!!! And I mean dead short, 0.6 ohms!!! This channel still worked, on scope it worked as well as the repaired channel, exact same AC output voltage when driving 8 ohm loads just below clip!!! I checked this after fixin the obviously blown channel. Not blowing rail fuse. Perfectly symetrical clipping of both channels. Anyone ever see this? I've never repaired an amp, any amp, that would still work with one output with a dead shorted EB juction on an output. All 0.1 ohm emitter resistors ok. None open. Reccomendations anyone for next step of troubleshooting? Have some time as getting order together for Mouser, etc, as I now need some more 15024 & 5's to pick thru.

Thanks in advance, Stevie
 
S/550E for PA

This's my S/550E with PA version ;) I cloned PCB from my S/550E last year but I changed supply rails to DUAL SMPS MODULE.

Thanks
Anadigit
 

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I have Threshol S/550E on hand and cloned it already !
I learned all of its schematic and trouble shooting, please you take a photo of your Amp ?

I can suggest you to repair step by step.

Thanks
Anadigit
Take a photo from and down size of your clone,please. How to try to clone citation XX ,my friend
The circuit is very simple as citation 22 and xII as see from photos and schematics..I have perhaps 50 hi-end amplifiers with express soft.I can send them to all friends
 
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