i have to admit i'm not at all familiar with that amp, so i'm not sure what all of their tone labels are referring to... however, some of them seem pretty standard.
1.Mid-Shift control - this probably refers to the specific midrange frequencies that are affected when you adjust it
2.Psycho-acoustic low end enhancement - not sure of this one, but it sounds like it's a low end bass boost to your tone
3.Transtube gainboost - not sure of this one either. maybe it introduces some tube-like overdrive if you turn it up?
4.TT Boost - have no idea
5. Gain - this generally refers to the input level that is driving your amp. the higher the gain, the louder (and closer to distortion) your signal will be going into the amp
6. Treble - this refers to the high end adjustment of your tone controls. turning it up makes your sound more cutting and 'crisp', so to speak.
hope that helps-
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