WMD Aperture (Eurorack)

Advanced band pass filter whose passband width is variable. There are separate resonance controls for the low and high pass which form the Aperture's bandpass and in addition there are two different feedback types with aggressive character. The resonance has a very distinct, nasal sound and allows for self-oscillation ofboth filters over at minimum five octaves. The module is almost entirely voltage controllable, even parameters which aren't covered by potentiometers.
On the whole it's a very versatile filter module with a vast range of tonal possibilities.

As already said the Aperture consists of a low pass filter and a high pass filter, which being connected in series form a band pass. The cutoff frequencies are moved simultaneously using the 1V/Oct and Freq inputs as well as the Frequency- potentiometer, the passband width (= distance between low- and high-pass' cutoffs) is set with Width.
Cutoff position and passband width are visualized with eight LEDs.
Yet it is possible to control the cutoff frequencies of both filters individually by using the sockets HP CV and LP CV

The input level control is at unity gain in 12h-position, above that it amplifies the signal up to +6dB. This parameter is voltage controllable.
The Feedback parameter adds even more self-oscillation and a more aggressive, squelchy charachter. Its both modes color the signal in different ways and the feedback amount is voltage controllable as well.
Pretty much the only paramenter without voltage control is the dry/wet mix which allows for parallel filtering.