- Controls how much the filter moves in response to the input signal.
- Switch (not on all models)
- Switches between 2 input signal levels for use with active or passive instruments
there are 2 types of Chuck-A-Wahs: one using a LED and photo resistor to control the filter, the other using a FET (with high / low band switch).
The Chuck-a-Wah was made from 1975 to 1977.
a 1977 Colorsound brochure
An interesting device for use with electric guitars, bases, pianos and organs. The unit has a special type of sound filter triggered by the output of an instrument, the harder you play the more effect obtained.