iv got a dsl401 amp and had been playing it with the overdrive volume down at 2-3 and the master volume turned up to about 7, today i decided to try turning the overdrive volume up to about 7 and the master volume to 3, to me this sounded alot better, before i would play with the amp on od2 but now i have it on od1, i alway thought it was ment to be the master volume that was set higher and the volume lower to get a good sound? or was i doing it wrong before?
master volume higher is more for a clean sound and when cranked true powertube distortion, other way around gets your preamp gain.

i prefer just cranking a master.
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If you want to drive your amp, you generally turn the drive channel up. Master volume is only for how loud you generally want it to sound. Master volume only starts driving the speakers for speaker distortion when it's up high. You won't get crunchy preamp distortion by raising the master volume alone.
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