Witch Finger

The Witch Finger is a nonlinear op-amp amplifier in October Audio’s mini enclosure, named after those plastic Halloween witch fingers because the Davies fingernail-style knob looks the part.

Volume increases logarithmically from just over unity to about 10dB of clean gain before symmetrical diode soft clipping engages around 1 o’clock for another 5dB of boost. The left half of the knob is clean gain suitable for preserving signal against high-frequency loss, pushing an amp to breakup, or boosting an effects loop. The right half layers in progressively more overdrive as clipping ramps up exponentially toward maximum.

One knob controlling a dual potentiometer (gain and diode clipping simultaneously). 3.63 x 1.50 inches, 255g. Runs on 9V center-negative at 3mA, no battery.