“The Electro-Harmonix Octave Multiplexer pedal from the mid-1970s. This is the [perhaps] very rare “treadle version” with the circuit housed in a wah-wah style chassis rather than the standard trapezoid EH box. The controls feature range switch, high filter pot, bass filter pot, bass plunger switch and bypass switch. This is the same circuit as the standard EH Octave Multiplexer, except with this version the dry/effect blend is controlled via the treadle rather than a stationary pot.”
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