F5 power amplifier

I reversed after the caps, they should have seen nothing but a lot of current going besides them?

I can adjust currents and voltages across the resistors just like before, so there should be all ok with those? If they were much off their nominal value, it wouldn't hum because of that I think?
 
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top view. Earth is off-center (see bottom left), I tested without earth, too, and without NTC. Replaced the recitifier, too. Also bridged resistors between the caps.
 

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Good suggestion is to take out all wiring in power supply and to signal boards. Start again. Easy to make wiring mistake and tough to find when you test everything at the end. Try to route wires in a bundle, use non-metalic bag ties or tie wraps when completed.

It doesn't take much to blow up a high current amp, especially with point to point wiring.

Good luck.
 
Wish I could see something but I can't. It's been my experience that while focused on fixing one area the physical activity may force a break (cold solder joint etc.) or short elsewhere. If it were my project I'd pull back to the individual sections and add them back in one at a time.

Good Luck!

Edit: Ya - What they said :) I do admire your point to point approach:up:
 
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Ex-Moderator R.I.P.
Joined 2005
It's my understanding that 'most' hum problems turn out to be ground related.

I guess it might be possible
a curcuit might cause small amount of hum if not well adjusted so that part of a curcuit is working outside its optimal
have experienced this with other curcuit a few times
but that would be speculation here
and I'm really a no-nothing when it comes to this :D