I added a 47pf cap across the PI plates and it helped a lot.
Then I decided I wanted to add adjustable global feedback ala the presence control.
It was late and after I had it wired up, flipped the switches and.....HOWL...
I couldn't work on it after that because the wife was in bed.
I haven't verified it yet but I am thinking that the two plate resistors of the PI are backwards, in other words the 82K is where the 100K is, and possible the OT wires are backwards, although I had flipped them before.
But, it's kind of fun having an amp to mess around with that I don't really care if it blows up, trying different things with it.
