Originally Posted by
Marcel
Thanks Doc... the circuit is very useful as the circuits I have are difficult to read hand drawn versions and don't include the wiring in the actual foot switch.
Initially I was only interested in how the switching was done so I could incorporate something similar in my AC18W build to swap from a 12AX7 input tube to the EF86 tube, but over the course of the afternoon I've been increasingly tempted to gut my 2204 build and step it up to a build not unlike yours as a 50W SLO-100 type build or more probably a 50W hot rod. As my 2204 build originally in a former life had 6L6's and the output transformer is impedance matched for 6L6's I'll probably pull the EL34's it's currently fitted with mostly as due to Z issues there have been moments where my 2204 is not happy with the load it get presented with. I have a Marshall with EL34's so some new tones will become available if I do make the swap in this build from EL34's to 6L6's...
Keeping the T/P switch is a good idea, If I go ahead then I'll probably keep the PPIMV control that is already in my 2204 build.