ajh-synth/gemini-2412-svf

Gemini 2412 SVF

AJH Synth

Dual multi-mode VCF featuring two independent vintage SEM-style 12dB state variable filters with a central mixing bus enabling serial, parallel, and inverted parallel modes; includes CV control of resonance, overdrive, and self-oscillation.749

Capabilities 1

State-Variable Filterstate-variable-filter
Dual vintage SEM-style 12dB state variable filters with LP, BP, HP, and VARY (LP-to-Notch-to-HP) outputs; can be cascaded for 24dB response.749

Jacks 16 (7 in / 9 out)

NameSignalVoltageDescription
Inputs (7)
1V/Oct 1cv749
D-FCVcv749
FCV 1cv749
FCV 2cv749
IN 1audio749
IN 2audio749
MIX CVcv749
Outputs (9)
BP Out 1audio749
BP Out 2audio749
D-OUTaudio749
HP Out 1audio749
HP Out 2audio749
LP Out 1audio749
LP Out 2audio749
OUT 1audio749
OUT 2audio749

Parameters 15

NameTypeRangeBehavior
AUDIO MIXknobCrossfades the D-OUT output between VCF1 and VCF2 outputs. Can be voltage controlled via the MIX CV input.749
D-FCV LevelknobControls the amount of D-FCV input (or internal voltage when no cable is patched) sent to both filters. When no external CV is patched, acts as a manual offset for both filter cutoffs.749
D-FCV MixknobControls the balance of D-FCV signal sent to VCF1 vs VCF2. Centre position sends equal amounts to both; fully CCW sends all to VCF1; fully CW sends all to VCF2.749
FCV 1 LevelknobAttenuverter for FCV 1 input. At centre (12 o'clock) no modulation passes; clockwise applies positive modulation to filter cutoff; counter-clockwise applies inverted modulation to filter cutoff.749
FCV 2 LevelknobAttenuverter for FCV 2 input. At centre (12 o'clock) no modulation passes; clockwise applies positive modulation to filter cutoff; counter-clockwise applies inverted modulation to filter cutoff.749
Filter Mode Switch 1switchFour-way rotary switch selecting LP, BP, HP, or VARY to route to the OUT 1 jack and central mixing bus.749
Filter Mode Switch 2switchFour-way rotary switch selecting LP, BP, HP, or VARY to route to the OUT 2 jack and central mixing bus.749
Freq 1knob749
Freq 2knob749
IN 1 LevelknobControls VCF 1 input level. Positions up to 8 keep the sound clean; above 8 overdrives the filter core.749
IN 2 LevelknobControls VCF 2 input level. Positions up to 8 keep the sound clean; above 8 overdrives the filter core.749
INVERT Switchswitch749
Mode Switchswitch749
Vary 1knobSweeps the VARY output of VCF1 continuously from Low Pass through Notch to High Pass.749
Vary 2knobSweeps the VARY output of VCF2 continuously from Low Pass through Notch to High Pass.749

Firmware history 0 versions

No firmware history recorded.

References 1

  1. [749]
    AJH Synth Gemini 2412 SVF product pageproduct_page
    verified 2026-05-22