Does this exist?
I do not do volume swells with my volume knob. I do, however, roll the volume knob down to clean up my amp. I would think it'd be cool to have a volume knob with either detents that are easy to feel, or a knob with say 5 or so positions to click into, to get an exact gain level.
The only problem I could see would be that the levels of the switch might not be the levels of gain you want, but other than that, it would be cool.
Another idea would be a volume knob with a "memory" setting, to instantly recall a particular point on the potentiometer.
I don't know. I'm just thinking, because yesterday I was doing doing a lot of this, but regular volume knobs are inaccurate for getting a precise amount of gain.
I have a Morley volume pedal that has minimum volume settings for this purpose. I really just use the knob most of the time though.