So in the interests of more Rumble education, if gain is set to zero ie off then is the preamp essentially bypassed and the "sound" produced only by the power amp? Yet another nice Rumble "stock" sound, by the way.
These are my settings. Bright and contour switches on. Gain is at zero.
Sounds mega and punchy to me. Replacing the "gain" knob with the dirt level/section.
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