C4RBN by WMD is an analog 12/24 dB Multimode filter with input saturation and output wavefolder. The sound character of the filter ranges from nice and clean filtering to acid-like screaming sounds. The resonance extends to self-oscillation in all modes and is tonally playable thanks to temperature compensation. Part of the innovative filter is a switchable saturation for the audio input and a wavefolder for the 4-pole output. Long-term WMD fans will still know and love this feature from the old Synchrodyne filter. A special feature is the Ping input which triggers a fast Decay envelope with fixed decay time when a Gate or trigger signal arrives and emulates the behavior of a Vactrol circuit. In short, with C4RBN realistic sounding Buchla bongos are no problem. For Bandpass and Highpass there are 12 dB filter outputs, the Lowpass even has 12 and 24 dB outputs.