hi there, I'm back - and still having noise problems.
Good news is that I finally found out where (at least a part of) the hum came from.
Here's a picture of the now final interior of the case:
I shifted the AC wires from the 30-0-30 torroid a bit and the hum was much less - crazy.
Now there's still some kind of buzzing noise, higher pitched than the usual 50Hz hum.
Apart from that, there's no hum or noise even with open inputs and fully open pot.
I'm doing some testing at the moment since the noise is extremely sensitive
to how the wires from the torroid are routed...
Tried several variants now, gave some more twist to the already braided wires...
Tried alternate and normal grounding scheme again, also asymetrical.
No change, except that hum and buzz are changing a bit depending on how
I arrange them at their origin at the torroid.
Now I found that I can actually "feel" the torroid, I clearly feel it's vibrations.
Maybe I have to get another torroid?
This amp is driving me crazy.
Edited by Sathimas - 3/19/14 at 3:11pm