“The FX-85 Harmonic Enhancer was the 11th DOD FX-series pedal to be introduced, and one of the last to sport “bars” graphics. The FX-85 was the first DOD pedal to feature a “presence” control (allowing the user to “adjust the amount of harmonic enhancement”, according to the manual). This feature was subsequently integrated into the circuit of several later distortion pedals, starting with the FX-56 American Metal. The FX-85 debuted in early 1984, and was discontinued by 1987.”
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