Maybe more of a musical instrument than a piece of outboard gear, the Sherman FilterBank is a new powerful "process synthesizer" made in Belgium. Essentially the unit is an analog synthesizer where the oscillator sound source is replaced by any external signal source such as a sampler, guitar or pre-recorded music track or loop. The FilterBank is centered around two identical 12dB per octave voltage controlled filters with extensive routing and mixing of both on-board ADSR, LFO, AM and FM modulation sources. External MIDI controllers can also be used to modulate and change the sound but MIDI input is not required for good operation.

Both the filters in a single FB can be either used in serial or parallel with the ability to mix the amount of the serial and parallel signals. In serial mode you get a 24dB per octave filter for very fluid and unusual sound treatments. Filter types are continuously variable from low pass to bandpass to high pass filters all with very good resonance and modulation phase control. The two filters operate independently (Free) or can be synchronized (Sync) where Filter 2 slaves to Filter 1 tracking and processing the same frequencies. The Harmonics knob allows the two filters to sync but at pre-set musical intervals. Filter 2 could track a perfect fifth lower in frequency than Filter 1's set frequency. Other intervals include: octave down, two fifths down, two octaves down, two octaves down plus a Minor third, three octaves down, etc. It will be obvious from the well-written manual that a good understanding of filters, ADSR's and VCA's is important if you are to get the most out of this box. However I was able to get great operation the first time I used unit on a remix project without reading the book!

Filter modulation sources include: the on-board LFO that offers frequencies from 1 cycle a minute up to 3kHz with phase control over the depth; an FM input; the ADSR that can be switched to an Envelope Follower for the best "Mutron-type effects"; Filter 2 can amplitude modulate (AM) the two output VCA's for interesting Ring Modulator noises; external jack input insert points and other paths. All external MIDI controller data will add (or subtract) from front panel control settings.