capacitor divider vs capacitor selector. what's best?

[pietro_moog]

hi guys. i'm ready to build some stuff again, and this question pops up in my head.
what's the difference in sound between a capacitor selector and a capacitor divider made with a potentiometer?
when is it preferable to use a capacitor selector?
what's best in a circuit like the fuzz face? or a range master?

[Nocentelli]

https://www.diystompboxes.com/smfforum/ ... c=102098.0

When you go putting blend pots in there, the resistances in the non-full-on positions are no longer negligible. They cause frequency rolloff and shelving effects that may or may not sound like a variable cap like you've described. This may be good or bad, but it's not all variations between two caps. Also, the non-negligible nature of the resistances mean that they interact with the source impedance driving the input and the input impedance loading it. Again, this may not be bad, but it is not all variations between two caps.

I imagine that for circuits (like the EHX big muff pi) that have a series resistor at the input, the extra series resistance that arises from using a capacitor blend pot on half-way is not likely to critically affect the sound of the circuit since one would just be increasing the series input resistance that was already there. Something like a fuzzface, where a variable series resistance "smooth" pot is often added as a mod, an input cap blend pot would act both as a high pass filter, and would affect the distortion characteristic beyond what you would expect from simply removing some low end from the input signal.

I personally prefer a blend pot to a switch, purely because it takes up roughly the same amount of space, and gives more variety. Also, a pot is tweak-able, but whenever I have added a switch to a pedal in the past, I have ended up with a favourite setting that I stick to, so the switch then seems redundant.

[pietro_moog]

supercool! this answer is great.i have to study it, crazy, i didn't expect this. thanks.