Dual Duality Processing Filter

Dual Filters

Each filter from the 'Dual Duality Processing Filter' module is based
around two unusual and quirky low pass filter circuits that operate
either together or against each other.

The cut off frequency of each filter can be controlled by a common control voltage and the front panel's Frequency pot.
The second filter's cut off frequency can also be offset from the first.
This can be done with either the Offset pot or an offset CV.

The two filters work in parallel on the audio input signal.
The output of the first filter is then passed directly to the output but a
proportion of the second filter may be added or subtracted from this.
The level of the second filter is controlled by the Duality pot.
In the middle position the Duality pot allows no audio to come from the second filter.
Fully clockwise the second filter is added to the first filter's output.
Fully anti-clockwise the second filter's output will subtract and cancel out those
parts of it that are common with the first's output.

A wide variety of tonal responses can be made;
from the traditional low pass filter and band pass
sounds to complex vocal like formants.

This particular module is ideal for percussive synthesis/processing or
soundscapes,also having two identical filters in parallel together with the flexible
input routing rich complex modulated true stereo or stereo/mono combined processing is
possible.

Features:

Each filter has:

-One audio input with level control.
-One fixed cv input 'v/oct'
-Two cv inputs with level control.
-Frequency,Q,Offset and duality controls.
-One offset cv input with level control.
-One audio output.

-Additional 3 audio input mixer with level controls,
the internal output of this mixer can be routed independently to
both filters via dedicated hi quality illuminated
push button switches.

-Additional output mixer with control levels for each filter output
so the outputs from the two dual filters can be mixed 'on board' to
a single audio output jack.