Surges from Behringer is the 1:1 reincarnation of the popular Mutable Instruments Ripples Multimode filter. There are two audio inputs: the one without knob has a soft character, the input with knob tends to distort heavily depending on the setting, which is a great addition in terms of sound. The slope of the lowpass and bandpass can be switched between 12 and 24 dB; for the highpass, this value depends on the resonance. The last element in this module is the built-in VCA, which is positioned behind the filter and permanently connected to the lowpass output. There are two CV inputs to control the Cutoff parameter, one each for resonance and VCA level. The VCF/VCA combination makes it ideal for smaller systems and space-saving setups.