![Wink :wink:](./images/smilies/icon_wink.gif)
And whenever I put a 12ax7 in the phase inverter, it makes the amp hum.
The hum is present with the volume turned all the way down. It goes away as your turn the volume up to about 2 or 3, But then returns around 4.
It sounds kind of like bad filtering. But i've tried bumping up the filter caps, and it doesn't seem to help.
If I put a 12au7 in the phase inverter, it goes away. Actually, with a 12ay7 in V1, and 12au7 in V2, its a super clean little amp. But i do want to be able to crunch it up, and get the rocks tones.
I made the amp to 5e3 specs. with a few mods.
-one input through 68k resistor
-V1 is permanently wired in paralell, with the plates tied together with a single 220k resistor, cathodes together like stock
-no tone pots, just a volume. so from the 220k plate resistor from the first gain stage, its goes to a 100n coupling capacitor to the 1Ma volume pot, to the input of next gain stage.
Then the rest of the amp is stock.
any ideas as to what is causing the hum when the 12ax7 is plugged in?
thanks!