For lowish volume practice I can currently run the SC20H on 20W mode with the master at about a 1, or just slightly above that on 5W mode (maybe just under 2) with the preamp at around 8 in both cases. Is there any benefit to getting an attenuator to be able to run the master at higher volumes?
While I am asking: Does the poweramp distortion of the amp behave differently in the 5W mode vs the 20W mode? I.e., in 5W mode does the power amp distort at lower numbers on the master volume than in 20W mode? For both modes, what is a good number at which above power amp section distortion is occuring (not factoring in specifics like pickups, etc)?