The Vermona DAF-1 is a Dual Analog Filter. It's a stereo filter with two individual high/lowpass 24dB/oct filters on each channel. They have the standard frequency cutoff and resonance controls. The two filters can be linked into any of four modes: Band, Notch, Parallel, and Serial.

In Band mode filter 1 is a highpass, and filter 2 a lowpass. In Notch mode filter 1 is a lowpass and filter 2 is a highpass. In Parallel mode both filters are lowpass. In serial both are also lowpass but since the signal flows first through filter 1 and then filter 2, you get a 48dB/oct slope! In this mode you can patch the left channel's output into the right channel to send a mono sound source through all four filters for a 96 dB/oct slope!! Did we mention this was an analog filter?

There is an on-board LFO to modulate the cutoff frequencies for each filter. There is also a CV input jack which works either as envelope follower, or with an external control voltage or volume pedal. It also uses TRS (MONO/STEREO) input/output jacks. It's not as dirty or programmable as the bigger Sherman or Mutator filters, but it's an affordable alternative.