This is the Voodoo of the Guitar World, indeed.
What is the difference between audio taper and linear taper potentiometers?
Traditionally, audio taper pots have been used in volume control positions and linear taper pots have been used in tone control settings.
The AUDIO taper increases the signal from your guitar to your amp in a logarithmic fashion. (exponentially) The LINEAR taper pot increases the signal in a linear fashion. (“1” on your control is equal to 10%, “4” is equal to 40% and so forth)
As a general rule (and this depends on the listener), volume control tends to sound better when it is funneled through an audio taper pot. There seems to be more control over the swell created when rolling the volume knobs up or down. And the quality of the pot also makes a BIG difference in how the signal is increased or decreased. CTS pots, in our experience, seem to give better control & a more reliable signal of all the pots that we’ve tried. (Bourns, Alphas, RS, CTS)
So, in conclusion… (and generally speaking, of course) AUDIO taper for volume controls. LINEAR taper for tone controls.