Optomix rev2 2016

Make Noise 8HP
VCA VCF FILTER UTILITY MIXER

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Two-channel vactrol low-pass gate with STRIKE and DAMP. rev2 adds audio-rate DAMP (sidechain compression), CV offsets on signal inputs, and drops CH1→CH2 normalization. Chainable via AUX.

Patch Ideas · 7

★ Bongo (PP + FM + LPG)
Touchplate-played bongo: FM source into CH 1, Pressure Points Common Gate strikes, CH 3 Gate adds dampening mid-decay.
Walkthrough
  1. On your VCO, patch a sine wave into its own Linear FM input to make a two-operator FM tone.
  2. Patch the VCO main out → Optomix CH 1 Signal In.
  3. Set CH 1 CONTROL knob full CCW (so the vactrol is closed until struck).
  4. Set CH 1 DAMP knob to ~9 o'clock (gentle dampening baseline).
  5. Patch Pressure Points Common Gate → Optomix CH 1 STRIKE.
  6. Patch Pressure Points CH 3 Gate → Optomix CH 1 DAMP CV.
  7. Patch Optomix CH 1 Signal Out → your monitor input.
  8. Tap PP touchplate 4 to pluck the bongo; tap touchplate 3 during decay to palm-mute.
Signal out Optomix CH 1 Signal Out — plucked FM bongo tone, up to 10Vpp.
Listen for Each touchplate 4 tap produces a short, woody FM bongo with natural decay. Holding touchplate 3 during the tail clamps down on the ringing like a hand on a drum head. The DAMP knob sets how hard touchplate 3 mutes — CW is drier, CCW is barely there.
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 4 connections. Modules: Optomix, VCO, CH 1, Pressure Points, Output. Signals: 2 audio, 2 gate.OptomixVCOCH 1Pressure PointsOutputCH 1 CONTROL: full CCWCH 1 DAMP: ~30% (set dampening)OutaudioSignal InaudioStrikegateDAMP CVgateOutaudioCommon GategateCH 3 GategateInaudio1231. FM source2. touchplate 43. touchplate 3 dampensaudiogate
★ FM pings
CH 1 processes a sine, its output drives another VCO's Linear FM input. Each STRIKE trigger pings a short FM burst.
Walkthrough
  1. Patch VCO A sine out → Optomix CH 1 Signal In (audio-rate).
  2. Set CH 1 CONTROL knob full CCW — the vactrol stays closed at rest.
  3. Set CH 1 DAMP knob to taste (12 o'clock is a good start).
  4. Patch a trigger/gate source → Optomix CH 1 STRIKE.
  5. Patch Optomix CH 1 Signal Out → VCO B Linear FM input.
  6. Play a note on VCO B and fire triggers — each trigger pings a burst of FM.
  7. Turn DAMP CW for tight, percussive clicks; turn CCW for longer modulated sweeps.
Signal out Optomix CH 1 Signal Out — pinged sine, gated by the vactrol, into VCO B Linear FM.
Listen for Every trigger drops a quick, decaying modulation burst into VCO B's pitch/timbre. With DAMP low you get a percussive 'chirp'; with DAMP high you get a longer FM sweep per strike. Works with LFO, random, or noise sources as the CH 1 input for chaotic bursts.
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 3 connections. Modules: Optomix, VCO A, CH 1, Trigger Source, VCO B. Signals: 1 audio, 1 cv, 1 gate.OptomixVCO ACH 1Trigger SourceVCO BCH 1 CONTROL: full CCWCH 1 DAMP: to tasteSineaudioSignal InaudioStrikegateOutcvTriggateLin FMcv11. dynamic FM pingaudiocvgate
Kick-drum ducked drone
CH 1 generates a kick whose output feeds CH 2's DAMP CV. Drone on CH 2 is sidechain-ducked; monitor SUM.
Walkthrough
  1. Patch a sine VCO → Optomix CH 1 Signal In (kick source).
  2. Patch your kick gate → Optomix CH 1 STRIKE AND → the same VCO's Linear FM input (for pitch-drop thump).
  3. Set CH 1 CONTROL knob full CCW and CH 1 DAMP to ~10 o'clock (short kick decay).
  4. Patch a drone source → Optomix CH 2 Signal In.
  5. Set CH 2 CONTROL knob to ~50% (this sets the compression ratio).
  6. Set CH 2 DAMP knob starting at ~12 o'clock (this sets the threshold).
  7. Patch Optomix CH 1 Signal Out → Optomix CH 2 DAMP CV (audio-rate sidechain).
  8. Patch Optomix SUM Out → your monitor; adjust CH 2 DAMP and CONTROL to taste.
Signal out Optomix SUM Out — kick plus ducked drone, up to 10Vpp.
Listen for The kick hits, and the drone ducks underneath it with a soft, squishy pump — then swells back in as the kick tail fades. CH 2 CONTROL around 40–60% gives the best ratio; DAMP sets how loud the kick needs to be before ducking kicks in.
▸ Show diagram
Patch diagramPatch diagram with 7 modules and 6 connections. Signals: 4 audio, 2 gate.OptomixVCOCH 1GateDroneCH 2OutputCH 1 CONTROL: full CCWCH 2 CONTROL: ~50%CH 2 DAMP: sets thresholdSUM OutaudioLin FMgateSineaudioSignal InaudioStrikegateOutaudioKickgateOutaudioSignal InaudioDAMP CVaudioInaudio11. sidechainaudiogate
Accent via dual envelope
Non-accent envelope → CONTROL for baseline dynamics; accent gate → STRIKE and → DAMP CV for louder, brighter accented steps.
Walkthrough
  1. Patch your VCO → Optomix CH 1 Signal In.
  2. Patch the sequencer step gate → your AD envelope's trigger.
  3. Patch the AD envelope out → Optomix CH 1 CONTROL.
  4. Set CH 1 CONTROL knob to ~70% (this attenuates the baseline envelope — leaves headroom for accents).
  5. Patch the accent gate → Optomix CH 1 STRIKE.
  6. Mult the accent gate → Optomix CH 1 DAMP CV.
  7. Set CH 1 DAMP knob to at least 20% (adds snap/brightness on accented steps).
  8. Patch Optomix CH 1 Signal Out → your monitor.
Signal out Optomix CH 1 Signal Out — sequenced voice with velocity-style accents.
Listen for Non-accented steps play at a normal level via the AD envelope. Accented steps jump in volume (STRIKE pings the vactrol harder) AND get a tighter, brighter attack (accent gate on DAMP speeds the decay). Classic velocity feel without a dedicated VCA.
▸ Show diagram
Patch diagramPatch diagram with 7 modules and 6 connections. Signals: 2 audio, 1 cv, 3 gate.OptomixSequencerEnvelopeCH 1AccentVCOOutputCH 1 CONTROL: ~70%CH 1 DAMP: ~20%GategateTriggateOutcvCONTROLcvStrikegateDAMP CVgateSignal InaudioOutaudioGategateOutaudioInaudioaudiocvgate
Palm-mute percussion
Gate strikes CH 1 AND triggers MATHS; MATHS' slow rise into DAMP CV clamps the ringing a moment after the pluck.
Walkthrough
  1. Patch your VCO → Optomix CH 1 Signal In.
  2. Patch your gate source → Optomix CH 1 STRIKE.
  3. Mult the same gate → MATHS CH 1 (or CH 4) TRIGGER input.
  4. Set MATHS CH 1 RISE to at least 60% (long rise — delays the mute).
  5. Set MATHS CH 1 FALL to less than 50% (quick return).
  6. Patch MATHS CH 1 Unity Out → Optomix CH 1 DAMP CV.
  7. Set Optomix CH 1 DAMP knob to at least 65%.
  8. Patch Optomix CH 1 Signal Out → your monitor.
Signal out Optomix CH 1 Signal Out — plucked tone with delayed palm-mute clamp.
Listen for Each gate plucks the vactrol and opens the tone brightly; a moment later MATHS' rising envelope arrives at DAMP and clamps the ringing down — exactly like a palm landing on a guitar string after the pluck. Raise MATHS Rise for later mutes, raise DAMP knob for a harder mute.
▸ Show diagram
Patch diagramPatch diagram with 6 modules and 5 connections. Modules: Optomix, Gate Source, CH 1, CH 1, VCO, Output. Signals: 2 audio, 1 cv, 2 gate.OptomixGate SourceCH 1CH 1VCOOutputCH 1 DAMP: ~65%Rise ≥60%, Fall <50%GategateStrikegateDAMP CVcvSignal InaudioOutaudioTriggateOUTcvOutaudioInaudio11. delayed palm muteaudiocvgate
★ Two-voice LPG mixer
Voice 1 → CH 1, Voice 2 → CH 2, each with own STRIKE and DAMP. SUM Out gives the mix; AUX can chain another LPG.
Walkthrough
  1. Patch Voice 1 → Optomix CH 1 Signal In.
  2. Patch Voice 1's gate → Optomix CH 1 STRIKE.
  3. Set CH 1 CONTROL full CCW and CH 1 DAMP tight (CW) for a short pluck.
  4. Patch Voice 2 → Optomix CH 2 Signal In.
  5. Patch Voice 2's gate → Optomix CH 2 STRIKE.
  6. Set CH 2 CONTROL full CCW and CH 2 DAMP CCW for a long, ringing tail.
  7. (Optional) Patch another Optomix/modDemix SUM Out → Optomix AUX to chain it in.
  8. Patch Optomix SUM Out → your monitor.
Signal out Optomix SUM Out — mixed CH 1 + CH 2 + AUX, up to 10Vpp.
Listen for Two independently plucked voices share one output — one tight and staccato, the other long and bell-like — with no external mixer required. Chaining via AUX lets several LPG voices fan into one master SUM.
▸ Show diagram
Patch diagramPatch diagram with 8 modules and 5 connections. Signals: 3 audio, 2 gate.OptomixVoice 1CH 1Gate 1Voice 2CH 2Gate 2OutputCH 1 DAMP: tightCH 2 DAMP: long ringingSUM OutaudioOutaudioSignal InaudioStrikegateTriggateOutaudioSignal InaudioStrikegateTriggateInaudioaudiogate
LPG as AD envelope source
Leave CH 2 Signal In unpatched (+8V offset). Strike CH 2 and the channel output becomes an AD envelope with VC decay.
Walkthrough
  1. Leave Optomix CH 2 Signal In unpatched (the +8V normalled offset is the envelope's ceiling).
  2. Set CH 2 CONTROL knob full CW (passes the full +8V offset through).
  3. Set CH 2 DAMP knob to your desired decay time (CCW long, CW short).
  4. Patch your gate source → Optomix CH 2 STRIKE.
  5. Patch Optomix CH 2 Signal Out → your target CV input (VCA CV, filter cutoff, etc).
  6. (Optional) Patch a CV → CH 2 DAMP CV for voltage-controlled decay time.
  7. Fire gates — each one produces one AD envelope shot at the output.
Signal out Optomix CH 2 Signal Out — AD envelope, ~0–8V, fixed-fast rise + DAMP-controlled fall.
Listen for A clean AD envelope shaped like any vactrol LPG decay — fast attack, natural exponential-ish fall. Great as a spare envelope when no EG is free. Modulating DAMP CV gives voltage-controlled decay time.
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 3 connections. Modules: Optomix, Gate Source, CH 2, VCA, VCO. Signals: 1 audio, 1 cv, 1 gate.OptomixGate SourceCH 2VCAVCOCH 2 CONTROL: full CWCH 2 DAMP: decay timeCH 2 Signal In: unpatched (+8V offset)GategateStrikegateOutcvCVcvInaudioOutaudio11. Optomix as EGaudiocvgate

Behaviors

LPG (amplitude + frequency linked) CV → CONTROL

Simultaneous VCA + non-resonant LPF. As CONTROL goes positive, amplitude rises with low frequencies opening first; as it falls, highs disappear before lows. Creates natural acoustic-like attack/decay like a struck drum or xylophone bar.

STRIKE with DAMP decay gate → STRIKE

8V gate plucks the vactrol. Decay shape set by DAMP: CCW for long ringing, CW for fast muted pluck. Emulates drum-head palm-muting or guitar-string palm-mute without an envelope generator — the LPG becomes its own AD contour.

Sidechain compression (rev2) audio → DAMP CV + CV → CONTROL

Audio-rate at DAMP causes gain reduction. CONTROL sets the compression ratio (best ~40–60%). DAMP knob sets threshold. Soft, squishy ducking — route a kick's channel out into another channel's DAMP to duck a drone.

DAMP as accent accent gate → STRIKE + accent mult → DAMP CV

In sequencer patches, STRIKE alone accents by opening the LPG harder. Multing the accent gate to DAMP CV adds brightness/speed to accented steps, simulating velocity-sensitive attack. Non-accented env goes to CONTROL for body.

Envelope generator (rev2) gate → STRIKE, take output

Because CH signal inputs carry a +8V offset when unpatched, applying a gate to STRIKE and taking the channel OUT yields an envelope. Fall time = DAMP. Rise is fixed-fast. Works in a pinch as an AD envelope with VC decay.

CV offset / slew limiter signal → Signal In, CONTROL Combo Pot as level

+8V offset normalization on Signal In allows use as an offset generator, attenuator, or summer. An Optomix channel can also be a simple slew limiter with DAMP setting fall time (rise stays fast).

Vactrol speed characteristics any STRIKE/CONTROL modulation

Vactrols have moderate attack, slow decay, and non-matched gain between channels. Not suitable for clicks/pops or matched-gain stereo VCA duty. The 'ringing' sounds — especially on FM or ring-modulated sources — are the core character.

AUX chaining SUM Out of another LPG → AUX

Chain Optomix → Optomix or Optomix ↔ modDemix via AUX for larger mixes without external summing. AUX feeds SUM directly and is direct-coupled (CV works too).

Controls

CH 1 & CH 2 DAMP Sets ringing/decay response. CCW: long ringing. CW: muted, fast. Doubles as attenuator when DAMP CV In is patched.
combo pot · unipolar
CH 1 & CH 2 CONTROL Level knob for the vactrol VCA. Becomes attenuator for CONTROL Signal In when patched. Normalizes to +8V offset at jack.
combo pot · unipolar

I/O

IN · 5

  • CH 1 / CH 2 Signal In up to 10Vpp CV
    Direct-coupled audio or CV input. rev2: no longer normalled CH 1 OUT → CH 2 IN.
  • CH 1 / CH 2 DAMP CV 0V – 8V · normalized to +8V CV
    CV input for DAMP parameter. Audio-rate capable (rev2) for sidechain compression. DAMP knob acts as attenuator when patched.
  • CH 1 / CH 2 CONTROL 0V – 8V · normalized to +8V CV
    Direct-coupled, highly-sensitive CV for the vactrol VCA. CONTROL knob acts as attenuator when patched.
  • CH 1 / CH 2 STRIKE 8V gate expected GATE
    Gate input that plucks the vactrol — slow natural decay under DAMP control. No envelope generator needed.
  • AUX up to 10Vpp
    Direct-coupled summing input. Chain multiple Optomix/modDemix into SUM.

OUT · 2

  • CH 1 / CH 2 Signal Out up to 10Vpp
    LPG-processed channel output. Amplitude and frequency content both respond to CONTROL.
  • SUM Out up to 10Vpp
    Mix of CH 1 + CH 2 + AUX. Master output for chained setups.