Most volume and tone controls used in electric guitars are carbon type potentiometers and are used to select a desired proportion of the total voltage across the potentiometer. The potentiometer is an electrical mechanical device having two contacts connected at each end of a resistive element. The third terminal is connected to a wiper contact for selecting the desired proportion of the voltage and to mechanically change the voltage or output from the guitar to the amplifier.

Potentiometers can be Audio or Linear taper for the desired output or position of current at a particular point of contact on the component. 250 K Audio taper potentiometers are commonly used on Fender style electric guitars to compensate for the lower sensitivity of the human ear. 250 K Audio taper pots will cut more high frequencies than a 500 K Audio taper pot.