The Invention Of The Wah-Wah Pedal

After a few days of fiddling around with spare parts, Plunkett succeeded in designing a circuit that could change the frequency of notes by simply rotating a potentiometer. Then, something unexpected happened:

“I went next door, and asked a friend of mine to plug a guitar into this pile of wires, resistors, and capacitors I had on the bench. He strummed a few chords while I turned the knob on the potentiometer. It went ‘WAH-WAH-WAH.’ We looked at each other, and said, ‘Wow! This is really great!’”

And it looks like this :

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