popping (yep, that old problem)

[cloudscapes]

Hey all,

I just built a jawari, it unfortunatelly pops when engaging the effect, but not when turning it off. I have another design which is based on it that also pops but I thought I'd start with the original first.

I honestly searched, since it's a problem that arises often. The article on geofex, on AMZ and various threads here have fixes for when you use a LED, the sudden surge of current that causes popping. In my case it's irrelevant since I'm not using a LED, and the circuit is "always on". Basically, the stomps (which I bought from this site ) just bypass the circuit. I tried pulldown resistors on both the in and out, and the pop dissapeared only when I got down to about 2k or so (which is far too low for a stompbox). I tried a different stomp as well, in case it was defective. Same result.

I'm a bit unsure what I could do next.

[R.G.]

If you have to go to such a low value for a pulldown, it is likely that your input or output capacitor is inserted backwards if it's an electrolytic. If it's not electro, you have some kind of leakage. Do you need 2k at BOTH input and output, or will 1M do at one of them?

[cloudscapes]

I had completelly forgotten about the input cap. since the circuit "sounded good" I guess I thoguht I shouldn't touch the circuit itself. the input electrolytic was indeed backwards, and fixing it got rid of most of the pop. I put a 100k pulldown resistor for the input, and a 470k for the output, which got rid of the rest of the audible pop. looking at the waveform in 96/24 though and I do see a jump, but I can't hear it. I'll try it on my amp in a bit.

now to work on the led

thank you!

EDIT: actually, it seems to only pop one in four times (more likely if I wait a few seconds rather than switch right away)
still considerably better!

EDIT 2: yeah, now its doing it most of the time, and the circuit is unchanged from when I first posted thie first success. it's still a lot better than it was, I guess I just have to tinker some more.
an electrolytic cap on the output does absolutelly nothing