I am very confused about how to go about using my digital potentiometer to control an audio signal. I have a MCP4231 digital pot and I would like to use it as a MCU controlled variable resistor for gain control of a headphone amplifier. I know there are much better ways of doing this (such as special op-amps) but I would like to try this using the digital potentiometer.
So basically, I am VERY confused. Do I need a DC bias for the chip I am using? Why can the YouTube lady get away with no biasing? Should I use the method in the first link of the second one? THEN finally, once I choose a method, how do I choose my resistor values?
By the way, this is the circuit I am trying to control. The analog potentiometer that I want to replace is circled in red.