10 Alpha Pots?

[bobbass4k]

I have the feeling it's a dumb question, but a friend gave me his Billy Sheehan Deluxe Drive to fix (various issues) and it has Alpha Pots which are marked "10" before the actual pot value, so there's a "10C100K" and a "10A250K". I assume this means 10% tolerance but does anyone know for sure? Alpha's website is useless.

[GGBB]

It refers to the taper. More specifically the percentage of total value at 50% rotation between start and wiper. So 10 means 10% of value at 50% rotation - which for a 250k pot means 25k. It's a little confusing if you think about it too much because you'd expect A and C tapers to be opposite (10% would be 10A and 90C) but for C taper it's measured in the opposite direction between pin 3 and wiper.  See http://alphapotentiometers.net/html/taper_curves.html.

The higher the number, the flatter the taper. A linear taper pot would be 50.

[bobbass4k]

Ahh, that makes sense, thanks man. I always thought that was just called D Taper, didn't realize there was a different name/terminology for it.