I've had just v1, v1 and v2, v1+v2+pi, together.cobalt wrote:Are ALL pre amp and PI grounds going to the same grounding place/potential? Maybe a little cathode drive goin' on?
I've had each cap at a separate chassis point as well.
I just jumpered from first cc to stage2 grid effectively removing the gain pot, with a 1meg R clipped to ground. Still get guitar at speaker with v2 removed.
From previous post, jumping from stage1 plate to the TS eliminates the problem. So there is some sort of interaction between stages1&2 that somehow interacts with the rest of the amp. This only happens when both sides of the tube are employed. Decoupling the PS with an extra RC filter did not help.
Time to change the ceramic socket. If that doesn't work, I'm done with this thing.