Wah Wah Mods
Wah-Volume pedal mod
Lifting the earth connection of the 4.7µF capacitor will cancel the wah effect and leave you with a volume pedal. The wah circuit will thin out the tone in volume mode - to get around this, the '70s Jen Wah-Volume pedal switches in a 4K7 resistor and 0.22µF cap in series across the 0.01µF "sweep cap". This isn't a very useful mod in practice; if the pot is set to get a good wah sweep, it won't go silent in volume mode, and if it's set up to kill the volume, there won't be enough treble in the wah.