Back to Posts

Tel-Ray Morley Volume Pedal

Gretchen in hardware, pedal, volume pedal

It's an active volume pedal that runs on 120VAC. It's half a decade old and used to work, I swear.

IMG_0250
IMG_0255

The circuitry all floats inside. Your foot moves the pedal moves an arm that holds a little curtain: the curtain sits between an incandescent bulb (which doubles as an indicator light) and a photoresistor: the farther back you push, the less light reaches the photoresistor. The photoresistor joins the two 1/4" jack and so the volume is attenuated.

IMG_0265

By the way, there's no buffer, only a photoresistor between the input and output. Sometimes there are rumors that optical volume pedal design prevents "tone suck", but I don't think that's true here. The input and output impedances change with the pedal just like they would with a normal friction potentiometer...

Image-uploaded-from-iOS--41-

(The bulb's dead).

IMG_0270
IMG_0272

Gretchen. Sometimes audio research, sometimes security research.

Read Next

Aleph sound computer