Yamaha GEP50 Guitar Effect Processor

This is a Yamaha GEP50 Guitar Effect Processor, a 1U rack-mountable digital effects unit from the late 1980s. The device features a black metal chassis with the distinctive orange "GEP50" logo and "YAMAHA GUITAR EFFECT PROCESSOR" branding on the front panel. The unit includes various control buttons for memory functions (Store/Recall), parameter adjustment, compare, insert, utility, and bypass functions, along with an input level control knob and power switch. Two 1/4" audio jacks are visible on the front panel (Tuner Out and Input), with additional connections likely on the rear.

February 22, 2026