The Black 3109 VCF/VCA is Erica Synth's approach to capture and enhance the fat sound of old Roland synthesizers like Jupiter-6 or SH-101 . The usual high quality workmanship of the Black series is also noticeable in the 3109 VCF/VCA. The 24dB Lowpass filter is based on the AS3109 integrated circuit, a modern version of the IR3109 chip, which was built into some old Roland classics and tends to a charismatic coloring of the cutoff frequency at high resonance. The Cutoff parameter can be modulated via keytracking input and normal CV input including attenuator. In addition, the user can choose whether to work with or without level compensation. The audio output of the modules is equipped with an analog VCA, which is activated as soon as a cable is plugged into the VCA-CV input, in small systems "the one socket" saves a whole module!