Louder Than Liftoff

FET Filter Saturating EQ Colour

The FET Filter has been replaced by the Super Filter mkII, which includes all of the FET Filter's functionality.

The FET Filter module couples transistor saturation with two tone-shaping equalization circuits. A gentle high-pass filter feeds into a variable mid-range cut/boost. Both EQ stages as well as the FET saturation can be set with jumpers, so you can tailor the curves and texture to your needs.

The unique FET input stage can be set to "Clean" for just a touch of analog flavor, "Dirty" for thicker saturation and transient rounding, or bypassed altogether for clean equalizing.


  1. Discrete FET input
    1. Two bias settings: Clean and Dirty
    2. Bypass via jumper
  2. 6 dB/oct high pass filter: OFF, 72 Hz, 160 Hz, 340 Hz
  3. +/-12 dB variable midrange boost/cut EQ: 330 Hz, 500 Hz, 800 Hz, 1.6 kHz
  4. Class-A biased audiophile grade op pamps
  5. Can be configured as:
    1. FET saturator (no EQ)
    2. High pass filter (no saturation)
    3. Mid boost EQ for warmth or presence
    4. Mid cut EQ for clarity or resonance removal
    5. Filtered distortion device

    Fully assembled, calibrated, and tested by Louder Than Liftoff.


    FET Filter Frequency ResponseFET Filter Harmonic Distortion

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