I can't remember seeing the letter on the pot in my guitar, but yes, the audio taper (volume how we hear it) type of pot is what you want. There is a lot of talk about DIY pedals around here so I threw that out for completeness sake. I know othatn the company "alpha" that supplies most of the pedal builders adds the letter on a lot of theirs. I can't vouch for all of them though. There is another called a reverse audio taper, but I left it out because I didn't think it would be necessary.
Loge story short, use the audio taper, that is the way you hear things. That is how you want your volume knob to work.
Patrick
