Plug in a microphone or another instrument with a 1/4" cable and use the keys to retune the sound.  You can control the mix of vocoded sound and unaffected sound and add reverb before the final output.  The whole keyboard is tunable and features a latch mode for hands free operation.

Knob1: Keyboard Tuning

Knob2: Squelch

Knob3: Wet / Dry Mix

Knob4: Reverb Amount

Aux and Foot Switch: Toggle 'Latch' On/Off