Rather than start a new thread I figured I'd bump this one.
I just did a non-switchable "Bass Shift" mod - simply swapped C232 (V1a cathode bypass cap) from 15uf to .47uf. For anyone playing high gain metal this is a MUST HAVE mod. Stock, the SP can be dialed fairly tight, but that meant the Bass at 0 and mids below 3, give or take. Now you get a bit more mileage out of the Bass/Mid knobs, just the Mark amps. I'm actually surprised Mesa didn't include the Bass Shift option to begin with way back when.
Hardwiring it in is a sacrifice, however. The clean channel is a bit less bouncy, but still sounds fantastic. No sweat for me though, I bought it for high gain. Having a nice clean channel is just a bonus.
