Which volume should I crank up first the MV or the ch.volumes with the gains?
Hello Michael,
If you want the amplifier clean, you turn the master volume up higher then the channel volume, this will keep the amplifier sound clean until you hit the distortion level in the power amp. If you have the channel volume higher then the master volume this will cause the pre amp to distorte allowing you to have a overdriven signal but a lower volme levels.
Kind Regards
Marshall Support