If you look closely you can see the trim pot on the edge of each side of the main board close to the back panel.
Those blue trim pots close to each other on a daughter board are protection circuits.
That’s good couldn't see the daughter board in my pic
Still going to have to get to the underside of those emitters, if they aren’t +speaker
Yes, speaker + terminal works:
And the picture on each channel you can see the protection pcb on standoffs:
I would personally do a lot of turned off and disconnected resistive tests first, to not apply power again, at all.
To compare resistance point checks from one channel against the other.
That’s probably the most safe and reasonable way to proceed.
Like an emerg doctor, I only get to see lots of newly and nearly dead things. In this case, lots of blown and nearly blown power amps.
A good few thousand of blown and nearly blown amps across my desk, tells me to proceed in this manner.
Fundamentally, do not turn it on again.
(Basically, audio designs look good when engineered and built. Elegant, even. But when all one does is deal with the broken end of it, then the flaws in the the given thinking design, and execution..... become quite clear.)
I experienced the same thing with a Bryston 14bsst amp. One channel would go rogue and get extremely hot, then the warning light would come on and shut down the amp. Sent it to Bryston repair and they said it was a bad bias and ended up replacing the entire left channel mother board (whatever that means!). It has worked perfectly since.