sys.14 | rhea is a resonant 18 dB/octave low-pass filter. It combines a warm, nonlinear filter response with strong resonance and a dedicated Squelch mode for a more pronounced, characterful response.

The cutoff frequency ranges from 30 Hz to 12 kHz and can be modulated over the full range using an external CV signal. The resonance circuit is carefully shaped to retain a powerful low-end response while becoming more pronounced at higher cutoff frequencies. Four-times oversampling, nonlinear feedback and soft saturation add further character to the filter.

The controls and their functions: from top to bottom:

• Cutoff: Sets the filter cutoff frequency from 30 Hz to 12 kHz.
• Resonance: Sets the amount of filter resonance.
• Mode: Turns Squelch mode on or off. Squelch adds a nonlinear feedback component for a more aggressive, pronounced filter character.
• Input: Audio input.
• Cutoff CV Int.: Sets the amount and polarity of cutoff CV modulation.
• Cutoff CV: Modulates the filter cutoff frequency.
• Output: Filtered audio output.

Designed for deep sweeps, resonant acid lines and everything in between.