A beautifully sounding and highly versatile Dual Multi-mode VCF:

Featuring two completely independent Vintage SEM style filters, with a central mixing bus for both audio and frequency control voltages that allow the two VCFs to be combined in both serial and parallel modes, and VCF1 can be inverted against VCF2. So the two VCFs can be combined to behave as a 24dB SEM filter, vocal formant filter, and much more!

Each of the two filters is based on the vintage SEM filter, with FET transistor buffers and features Low Pass, Band Pass, and High Pass outputs, plus a useful Vary output which can be faded from LP to Notch to HP. All outputs can be used simultaneously.

We have added some exciting extra features unavailable on the original SEM filter, including CV control of Resonance, overdriving of the VCF core, and full self-oscillation!

VCF1 and VCF2 each have a four-way switch to select LP, BP, HP, or VARY to the mixing bus; this is also available as an additional individual output.

In Depth

The AJH Synth Gemini 2412 is a 28hp wide Eurorack module, featuring two Vintage SEM style, state variable voltage controlled filters, along with a versatile central mixing bus which allows them to be combined in series, parallel, or parallel inverted modes. A dual, variable frequency control system allows single control of cutoff frequency of both filters, and the actual CV amount sent to each filter can be set using the D-FCV MIX control.

More information you can find here: AJH Gemini 2412 Dual SVF