Volume Pot values

[newfish]

Being slightly afraid of the maths I may unleash, does it really matter what value of pot I use as a divider-style volume control at the end of a circuit?

In terms of signal percentage allowed out vs. signal percentage going to ground, I'm not sure it would make mush difference to choose between, say, 10K or 500K.

What I'm thinking about more is the effective impedance of the output, and what effect the pot value has on this - and how this interacts with whatever's next in the signal chain.

BOSS pedals usually specify a 10K output impedance - and the SD-1 has, indeed, a 10K level control at the end.
Fuzz Faces, on the other hand, have anything from 100K to 500K. 

Also, if the rule of 'high input, low output impedance' is to be followed, are we, by chaining devices together, forcing a mis-match of impedances at each new box?

Or does this not really matter...?

[ayayay!]

BOSS pedals usually specify a 10K output impedance - and the SD-1 has, indeed, a 10K level control at the end.
Fuzz Faces, on the other hand, have anything from 100K to 500K.

Ahh, but that doesn't mean that's the output impedance of the pedal!  The output buffer on a SD-1 (or any Boss pedal) is what determines the impedance.  As evidenced by it (the buffer) always being active, in bypass or not.  

The tricky thing about using a volume pot as a suitable output impedance is that its variability can be a blessing or a curse, depending on the circuit.  

So, yes it matters.  It's often the difference between dull, muddy & unintentionally overdriven, and bright, thin & fizzy.  Find your potentiometer zen!  ...or include a buffer.  Ha!