Trivium

Weston Precision Audio 12HP
FILTER VCA ENVELOPE UTILITY

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12HP analog voice core with state-variable filter, VCA, ADSR, AD/AR envelopes, routing switches, and a sidechainable pre/post path for clean voices or driven percussion.

Patch Ideas · 5

★ Complete voice
Audio source into Audio In · Gate opens the envelopes · ADSR drives the VCA · ADSR also sweeps the filter in Post mode · a compact one-module voice.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 4 connections. Modules: Trivium, VCO, Sequencer, Output. Signals: 2 audio, 1 pitch, 1 gate.TriviumVCOSequencerOutputPre/Post switch: PostVCA source switch: ADSRFilter source switch: ADSRFilter type switch: Low PassCutoff CV1v/octGategateAudio InaudioAudio OutaudioOutaudioPitch1v/octGategateInaudioaudiopitchgate
★ Pinged percussion
AD/AR mode selected · high resonance · short attack and decay · the filter rings like a struck body and the VCA follows the same percussive contour.
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 2 connections. Modules: Trivium, Trigger, Output. Signals: 1 audio, 1 gate.TriviumTriggerOutputPre/Post switch: PreVCA source switch: AD/ARFilter source switch: AD/ARFilter type switch: Band PassGategateAudio OutaudioOutgateInaudioaudiogate
★ Self-oscillating lead
No audio input · resonance pushed up · cutoff tracks pitch CV · hold the VCA open and use the filter as a playable oscillator.
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 3 connections. Modules: Trivium, Sequencer, Output. Signals: 1 audio, 1 pitch, 1 gate.TriviumSequencerOutputPre/Post switch: PostVCA source switch: HOLDFilter source switch: ADSRFilter type switch: Low PassResonance: highCutoff CV1v/octGategateAudio OutaudioPitch1v/octGategateInaudioaudiopitchgate
Pre-drive distortion
Pre mode lets the VCA overdrive the filter input before the filter stage · a kick or bass line gets a harder edge and a rounder resonant peak.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 4 connections. Modules: Trivium, Bass VCO, Envelope, Output. Signals: 2 audio, 2 cv.TriviumBass VCOEnvelopeOutputPre/Post switch: PreVCA source switch: ADSRFilter source switch: ADSRFilter type switch: High PassAudio InaudioVCA Env CVcvCutoff CVcvAudio OutaudioOutaudioOutcvInaudioaudiocv
Envelope router
Use the ADSR and AD/AR outputs as two independent modulation sources · one can shape another filter while the other drives a VCA or delay feedback path.
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 5 connections. Modules: Trivium, Filter, VCA, Delay, Clock. Signals: 2 audio, 2 cv, 1 gate.TriviumFilterVCADelayClockFilter source switch: ADSRVCA source switch: AD/ARGategateADSR Env OutcvAD/AR Env OutcvCutoffcvOutaudioCVcvInaudioOutaudioInaudioOutgateaudiocvgate

Behaviors

Two envelopes Gate input

The gate triggers both envelopes, and each envelope is also available as a standalone front-panel output.

Pre/Post routing Pre/Post switch

Pre places the VCA before the filter so the filter can saturate. Post puts the filter before the VCA and lets the output stage add gain.

VCA source selection VCA source switch

The VCA can follow the ADSR envelope, the AD/AR envelope, or stay held open.

Filter modulation selection Filter source switch

The filter can follow either envelope, with the attenuverter deciding whether the move is positive or inverted.

State-variable response Filter type switch

Low-pass, band-pass, and high-pass responses are available from the same core, with self-oscillation strongest in low-pass mode.

Percussive AD/AR shape AD/AR mode button

The second envelope switches between decay and release behavior, with a slightly convex attack that suits pinged percussion.

Controls

ADSR envelope ADSR Attack Sets the attack time for the ADSR envelope.
1 ms to 7 s
ADSR envelope ADSR Decay Sets the decay time for the ADSR envelope.
1 ms to 7 s with CV
ADSR envelope ADSR Sustain Sets the sustain level for the ADSR envelope.
0V to 8V
ADSR envelope ADSR Release Sets the release time for the ADSR envelope.
2 ms to 7 s with CV
AD/AR envelope AD/AR Attack Sets the attack time for the AD/AR envelope.
1 ms to 7 s
AD/AR envelope AD/AR Decay/Release Sets the decay or release time for the AD/AR envelope.
2 ms to 7 s with CV
AD/AR envelope AD/AR mode button Selects whether the second envelope behaves as decay or release.
Decay / Release toggle
Filter Cutoff Sets the state-variable filter cutoff.
shared cutoff control
Filter Resonance Sets filter resonance and the edge of self-oscillation.
clean to self-oscillating
Filter modulation Filter Env Attenuverts the selected envelope before it reaches the filter.
center: zero · CW: positive · CCW: inverted
Routing Pre/Post switch Chooses whether the VCA sits before or after the filter.
pre-drive or post-filter
Routing VCA source switch Selects which control source opens the VCA.
ADSR · AD/AR · HOLD
Routing Filter source switch Selects which envelope modulates the filter.
ADSR · AD/AR
Filter Filter type switch Selects the filter response taken from the state-variable core.
Low Pass · Band Pass · High Pass

I/O

IN · 9

  • Gate >1.5V gate GATE
    Triggers both envelopes.
  • Audio In audio AUDIO
    AC-coupled audio input to the routing section.
  • ADSR Decay CV CV CV
    Voltage control over ADSR decay time.
  • ADSR Release CV CV CV
    Voltage control over ADSR release time.
  • AD/AR Attack CV CV CV
    Voltage control over AD/AR attack time.
  • AD/AR Decay/Release CV CV CV
    Voltage control over AD/AR decay or release time.
  • Cutoff CV CV CV
    Voltage control over filter cutoff.
  • Resonance CV CV CV
    Voltage control over filter resonance.
  • VCA Env CV CV ENV
    Scales the selected VCA control source.

OUT · 3

  • Audio Out audio AUDIO
    Main routed audio output.
  • ADSR Env Out 0-8V ENV
    Front-panel ADSR envelope output.
  • AD/AR Env Out 0-8V ENV
    Front-panel AD/AR envelope output.