It hit me just now. One of my favorite guitar fuzz pedals, the Malekko Plus Ultra 213, includes a foot-switchable all pass filter (which sounds badass, by the way). I'm just in the finalizing stages of building a Muff clone, and I got this crazy idea that I could build a standalone all pass filter to add to other effects. I found this schematic on Wiki:
But it has no values on the components and the Vin and Vout is a little confusing. It doesn't even list what kind of op-amp to use. Is this even possible? What would it end up doing (esp. to a clean signal?
) I would assume I could replace some of the resistors in that diagram with pots to allow a frequency sweep change (like one would do with an expression pedal and the 213). Any insight?
This is my first/second attempt at effects really. I don't use effects on my guitar (I have a Mustang III handling that) and I've never used effects on bass... and now I almost have a Muff and am planning this. (I do have pretty good electronics knowledge so I'm not a total butt.) Be kind to me