Rossum Electro-Music Evolution is an analog variable filter module for modular Eurorack synthesizers. The circuit is based on the E-mu Systems 2100 LPF filter developed by Dave Rossum, which is easier to use in evolution and which allows completely new filter characteristics to be created.

Genus Control

With this parameter the slope can be continuously varied between 18dB and 36dB. Of course, this can be controlled either manually via the rotary knob or via the control voltage. The selected slope is continuously displayed via LEDs.

species control

This parameter controls the filter input level, controlling the overload of the selected filter. In self-oscillation mode, this parameter modulates the output level.

Voltage controlled resonance with variable Q level compensation

The voltage-controlled resonance with variable Q level compensation allows adjustment between the resonance peak and the frequencies below the cutoff frequency, which would otherwise also be increased as soon as the resonance is increased.

Sine oscillator playable over ten octaves

Evolution generates an extremely accurate sine wave at full resonance, which can be exponentially tracked over ten octaves, making evolution a real competitor to the best oscillators.