Twin Peaks by Cella - Dual resonant filter for VCV Rack inspired by Rob Hordijk's design

Twin Peaks is a dual resonant filter inspired by the design of Rob Hordijk's TwinPeak filter and Klangbauköln's Twin Peak Resonator. The design is straightforward: the same input signal is passed through two resonant low-pass filters, A and B, and their outputs are subtracted, producing a band-pass response with two peaks. This design allows the filters to 'pass' each other, meaning it doesn't matter which filter has the lower or higher cutoff frequency — the signal still passes through.

While you can use this module for filtering sound sources, it is best suited for being pinged with a stepped signal at relatively high resonance, which produces pleasant percussive sounds. The module offers a few internal modulation options, such as frequency modulation using the incoming signal and cross-modulation of filter A's frequency by the output of filter B. There are also multiple inputs that support external signal modulation.

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