well first of all, its potentiometers (pots for short.) a stock jazzmaster will have two B1M pots in the lead channel, and one b1M pot (volume), one b50k pot (tone). however A1M pots are considered superior, and B1M pots were kept on the jazzmaster only for vintage correctness. its kind of like this: our ears hear things strangely. they have natural compression, so for us to hear a sound as twice as loud as another, the louder sound has to be 10 times louder for us to percieve it as 2 times as loud. A taper pots take this into account while B taper pots do not.
