FX13 Ring Modulator is fuzzy, buzzy and downright nasty little bastard designed to deconstruct your tone, which the Gonkulator certainly does. There are really two parts to the Gonkulator; a simple Distortion circuit, ala The Grunge pedal, and the Ring Modulator. The "SUCK" (Level) knob and the "GUNK" (Gain) knob work together to control the Distortion effect. Neither of these controls do anything to the Ring Modulator sound. The "SMEAR" knob is basically a Mix control for the Ring Modulator; at the lowest setting you hear no Ring Modulator sound at all, at the highest setting, you bring on the noise. The "HEAVE" knob is sort of a Master Gain control for the whole box. The FX-13, known as the "Gonkulator Modulator" is designed to add dimension to a signal by taking the frequency sum and difference of the signal and blending it with DOD's Grunge distortion (The Grunge effect is in parallel with the ring modulation, and can be mixed together at the output). The overtones the FX-13 produces are very "gonk"-like sound.
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