- April 14th, 2020, 10:10 am
Just a guess, but your Guitar part probably uses an Audio Taper, not a Linear Taper. What's the difference? A linear taper is just that. A straight 0 to 10k from end to end. Midpoint will be 5k ohms. Audio taper is more of a logarithmic curve to match the sensitivity of the human ear. The first 2/3 of rotation is a small change in resistance with a rapid increase (almost a straight line up) for the last 1/3rd.
The GB "volume" is providing a control voltage to the circuit that adjusts the output from the amplifier. I think the circuit is actually using a programmed "map" to make the output act like an audio taper.
Edit: Just looked up the instructions, I remembered correctly:
The volume control on this particular amp is based on a dc control voltage and has a nonlinear correction built in. An audio (logarithmic) taper pot can be used but will be more sensitive to volume adjustments.