Devolver Wah - A Boomerang/Noomerang circuit

[culturejam]

I banged this out because I wanted to use the Maestro Booomerang Wah as a "stuck wah". I had some input from B. Tremblay of runoffgroove.com on this one as well, since he had played with the circuit quite a bit. The result is basically a Boomerang, but with an input gain trimmer. I find that if the input gain is a little too hot, you get some nasty frequency peaks. With the trimmer you can dial it.

I call it Devolver because that is the Spanish verb for "to return" (like a boomerang).

Transistor selection doesn't seem to matter much. I've tried everything from 2N2222a on the low end to 2N589 on the high end. Same sound either way. Same output volume.

The Wah pot pads are spaced for a PCB-mount pot. Of course, you can use regular solder-lug pots as well. I've marked off where you could put standoffs as well, if you want.

You can use either the typical Vox/Crybaby 4-lead inductors or Fasels. For Fasels, you need to orientate the inductor sort of "catty-corner". Looks kinda cool that way, actually.

I also added a 33K resistor in parallel with the Wah pot (a la the Noomerang) so that the common 100K pot can be used in treadle wah enclosures. This makes it much more of a drop-in with a wah shell for those that want to use it in an old enclosure for "standard" wah usage.

The Zip file contains the layout, schematic, transfer image, and parts list.
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