Variable Capacitors: why does nobody use them?

[triskadecaepyon]

If we try to vary capacitince in a bunch of effects, why does nobody use Variable caps instead of rotary switches and such?

[Alpha579]

they are often large, and generally only come in very small values....i think....

[niftydog]

because the values that are available are completely useless for signals in the audible frequency range.

Trimmer caps are very small, both in physical size and capacitance.

Air vane caps are a whole different story. Large, bulky, heavy, but still only a few tens of picofarads.

[strungout]

What those guys said.

If you're interested tho, there's an opamp based "varicap" than stm posted a while ago. Search for "varicap" or "capacitance + multiplier" or "stm", you'll find it. that'S still big but the available capacitance is alot bigger.

[puretube]

http://diystompboxes.com/sboxforum/viewtopic.php?t=24307