Sensei Tim wrote
Instead of using a voltage divider on the output, what about a gain control that adjusts the feedback resistor to go from 0 to x times gain?
If you're talking op-amp based boost, a gain pot in the feedback loop will need to go from e.g. 100k to zero k: Problem is, a gain resistor of zero in the feedback loop gives a buffer (i.e. gain = 1) not a mute.