The Amp Garage

Hi I've posted before previously with issues with a bad pot to get says new-build noise issues. There are pics of this unit. I can try what you've suggested but why would this not be an issue with the 12au7?

I have a ceriatone express clone that sounds good and quiet but I currently have a 12au7 in the PI position. The minute I put in a 12ax7, it begins to produce low frequency oscillation no matter what the volume. I've tried different tubes with same result. SOS

These are the black generic ones you get from antique electronics. I've temporaraly replaced it with the same type so you have incosistancy

Caps are all the same brand. I did change out the cap going to the treble pot and the rumble stopped. Volume control is smooth and quiet now. This amp still is a little tinny/trebley and sort of out of control. Distortion is a bit fizzy and farty even with guitar volume low. But we're getting there.

which one?

just measured 24vdc on vol pot

the amp does not squeal and humming is very minimal. Moving the pot even a little produces a thunder crash

I reversed the OT primary with no change. mind you that this pot behaves like an old scratchy one but very loud

Well I followed your instrutions with no change. Still rumbles loudly with a slight turn of the vol or treble pots.

I pretty much followed the ceriatone layout. The amp has a slight hiss but I've all but eliminated hum by using an artificial heater CT. I'll post some pics

This is a new Express clone which works but horrific thundering noise from the vol and treble pots when turned. HELP