Apologies if this has come up before, I built a THCustom Effects tube driver V1.2, and would like to lower treble and bass controls by maybe an octave. The treble in particular just adds noise, rather than shaping my sound. I recognise the Baxandall tone circuit, but don't know which cap values to alter, and to what...
Much appreciated!
Capacitors 28–31 are the components to experiment with. Since larger capacitors will create a lower cut-off frequency, doubling those values is a good place to start. I'd recommend socketing the capacitors and experimenting, though. I don't have any personal experience with the tube driver, so I can't say with certainty what will sound best. Also, you may find that what sounds best to you are different values entirely.