Black Finger

The Black Finger is a guitar-level optical compressor that uses two vacuum tubes in its signal path. A toroidal transformer lets the tube stage work with a full 300 volts of swing, rather than the 9 to 50 volts found in many tube-flavoured pedals. This is intended to keep note attack intact while giving a warm, sustaining compression.

The optical compression circuit can be driven by two different light sources, an LED and a lamp, which gives two distinct compression characters. Level is set with input and output gain controls. A mechanical relay provides true bypass. The pedal ships with two Electro-Harmonix 12AX7 tubes fitted.

It is powered by the supplied 12AC-1000 power supply. The maker positions it as a portable alternative to rack-style studio compressors, and recommends it for amplified acoustic guitar. The model was discontinued in 2019, so it is generally found on the used market.