valvecaster/twincaster mod help?

[JanssonGuitars]

Hi!
I've been thinking about building the twincaster pedal. however i'd like to mod it to only have one gain pot controlling both tubes.
Is it as easy as just connecting pin 3A and pin 3B to the same pot?

[Kesh]

It will make a large negative feedback loop from U2a back to U1a if they share a cathode resistor. Not sure how this will affect things as low voltage doesn't work by the text book. If you do it you will probably have to half the variable resistor. .

[JanssonGuitars]

Okey, not quite sure what you mean with U1a/U1b? and by variable resistor you mean potentiometer?

Would it work better with a stereo pot? or maybe a trimpot to tube A?

[reverberation66]

dual ganged pot?

[Kesh]

Okey, not quite sure what you mean with U1a/U1b? and by variable resistor you mean potentiometer?

Would it work better with a stereo pot? or maybe a trimpot to tube A?

U1a is the first half of U1, etc, which is also called V1

When a pot is not used as a voltage divider, ie only 2 lugs used, it can be called a variable resistor

[Skruffyhound]

You could use a stereo(dual ganged) pot.

Could probably pull one out of any old hi-fi, volume control.

[JanssonGuitars]

Thanks! I'll try with a stereo pot