Well? Question as above. Bet it's not necessarily the case, but how do you tell without measuring equipment? I'm sure you can't!
Potentiometers will I reckon vary depending on how good they are or how the maker decides they want them to operate.
And of course there's the 'Lin' or 'Log' thing. How does that influence the situation?
And then there's the amplifier circuit. Does it necessarily give a flat response at an anticipated control position?
Yes. I'm asking 'cos I'm using an amplifier with tone controls (a rare experience ).