LDR wah's

[psiico]

I built a Phuncgnosis, love those auto-wahs but I figured it might be fun to have a more normal wah as well.  Since I don't have the means to construct a decent housing for a rocking type pedal I was looking at some of the LDR wah designs.  So far I've built on a breadboard the Photon Filter and the Idiot Wah from here:

http://www.geocities.com/tpe123/folkurban/fuzz/snippets.html

Neither worked.  I tried them with LDR's and with different value pots in place of the LDR's.  I didn't get any change in sound regardless of what I used or wether it had full resistance or none.  Anyone else get these to work?  Can someone explain how they work?  How does changing the resitance to ground make it wah?

On a side note I experimented with the Phuncgnosis circuit, putting a pot in place of that switch that chooses wah up or down allowed a wah sound when rotated but a ton of squealing as well.  Using just one side with an LDR did nothing.  Can someone explain what the envelope follower in that circuit does to make that one wah?  Is it another resitance to ground thing like in the Idiot Wah and Photon Filter?  I tried an LDR in place of the envelope follower, had no effect.

I've been trying a bunch of different LDR's I bought a mixed batch.

Tonight after work I plan to experiment with the Kechi-Wah, I love those breadboards.

[psiico]

Nevermind, I'm an idiot, lol.  I figured out how to get an LDR to control the Phuncgnosis, now to try something else, the Phuncgnosis isn't a great wah, sounds terrible on the lower strings.

For those wondering how to do it you put the LDR in series with the one red LED that goes to ground, leave out the switch and the other three LED's going to 9v+.  Also leave out the whole envelope follower circuit.