Mr. Quack envelope filter is a modded version of the Dr. Q, mostly to make it more sensitive to the input signal. This envelope filter is really “punchy” and is perfect if you’re looking for a funky sound, either if you play guitar or bass.
An Attack potentiometer has also been added to make the Mr. Quack more versatile, allowing you to set how you want the envelope filter to react to your playing dynamics. The Range knob sets the range of the frequency sweep: more range translates into more funkyness.
The Mr. Quack is a really fun effect pedal, and if you’re looking for an envelope filter you should definitely give it a try!
Download here the manual for the Mr. Quack Autowah Kit: