Hum and buzz

[loudthud]

With regards to the grounding of the pot, all the pots are currently just attached to the chassis by a shakeproof washer on the inside and a normal washer and nut on the outside. The back of all the pots are just "as is". The ground lug of the pot is connected to the ground point of the following tubes cathode resistor/capacitor network. Is this ok?

It should be OK. Try touching a metal screwdriver between the pot's case and the chassis. Any change in the hum?

[guittube]

It should be OK. Try touching a metal screwdriver between the pot's case and the chassis. Any change in the hum?

No change

I think I might have to go back a step and play around with the grounds.

[dchang0]

It might simply be that that stage or the preceding one is very gainy. I did everything I could to reduce hum by improving grounding on my reverb recovery stage, but it turns out I simply had way too much gain on the stage. So much that the tube itself was microphonic and picked up noise everywhere.

Fixed that and reintroduced NFB and found the amp to be whisper quiet.