Vulnerable Variable-Circuit Filter

Vary circuit structure along a continuum of designs to explore the full set of possibilities, crossing through elegant curves to inviable behaviors alike, with the Vulnerable Variable-Circuit Filter. Start with the frequency and bandwidth dials to automatically calculate coefficients for a tonal starting point, then diverge via the silver fine adjustment knobs to stretch the circuit structure, potentially beyond proper functionality. Or, jump right in and scan filter structures by directly manipulating the coefficient controls. The peaking feature allows you to mitigate the destructiveness of vulnerable topologies, which are of course the funnest to dabble in.

The frequency & bandwidth controls can be modulated, the fine adjustment divergence can too, and on top of that, the coefficients can be modulated on top of that with further CV control. Use envelopes to dip attacks into chaotic filter behaviors that swoop into resonance, use LFOs to shake tones into and out of screaming, or subtly balance modulations that aren’t exactly changes in frequency and resonance alone, but a more complex interplay.

Blend mix in the original signal with the thru button, quickly invert the response by flipping the phase button (blending input signal with inverted filtered signal), make comparisons with the bypass button, and set the volume with the output gain control. The bandwidth and frequency dials can output CV to the CV inputs of a second device so that their settings are coordinated, allowing you to chain units but operate them together with a single set of controls while obtaining steeper curves.

You’ll find nooks and crannies of beautiful tone, and then cross into unstable noise, and wander along an interesting path of mutation. Don’t count on this device for regular filter behavior, but take the opportunity to discover its wonderful irregularity. This is the filter for people who like to break things and experimentalists who want unrestricted access to ill-advised designs.