This preamp has 2 channels -1 button on footswitch – switches clean/drive channel and the 2nd-internal screamer(something like “tube screamer” -but gain control of it stays not only for “gain”itself, but mix screamer sound to normal that meens if the gain knob is turned to the left – you got almost normal sound as it is without screamer, and when gain knob is turn to the right – gain of creamer and affect of screamer is grow both/. knob “solo” add volume then 2nd button of footswitch is on.
The boost(very smoth +3bB of gain) and fx loops could be assined to 2nd button of footswitch as well.
so 2nd footswitch turn on and off screamer allways , but boost and fx loop – if you want – depends on assining switches on the front pannel.(on / off / solo button depending)
Footswitch goes with preamp. I would recomend add gate for more metal sound.
Regular price for that preamp (pcb version) with delivery costs 360euro. The hand-wired on turret board with selected parts will costs 480euro.