Messor

Cosmotronic 8HP
COMPRESSOR VCA FILTER DISTORTION

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Analog stereo VCA feed-forward compressor. Sidechain with HP/LP filter (10Hz–9kHz), ratios from off through limiting into over-compression, Warm tube-style soft-clip saturation, gain-reduction CV output, and a stereo VCA mode via Gain CV.

Patch Ideas · 8

★ Four-on-floor kick duck
Classic side-chain pump: kick triggers compression on a stereo mix, ducking everything under each beat.
Walkthrough
  1. Set Filter switch to LP, Filter Cutoff around 9 o'clock (~100Hz).
  2. Set Attack fast (~8 o'clock), Release ~200ms (noon), Ratio ~3 o'clock (heavy).
  3. Threshold around noon — adjust until LED ring shows clear ducking on each kick.
  4. Patch your stereo mix → IN L / IN R.
  5. Patch the kick voice (or its trigger fed through a VCA) → SC IN.
  6. Take OUT L / OUT R to your output / next stage.
Signal out OUT L / OUT R — stereo mix audio with rhythmic ducking. Patch into your master bus.
Listen for Every kick hit briefly ducks the rest of the mix and breathes back over ~200ms — the classic 4/4 sidechain pump.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 5 connections. Modules: Messor, Mixer, Kick, Output. Signals: 5 audio.MessorMixerKickOutputFilter: LPFilter Cutoff: ~100HzAttack: fastRelease: ~200msRatio: 4:1IN LaudioIN RaudioSC INaudioOUT LaudioOUT RaudioOut LaudioOut RaudioOutaudioIn LaudioIn Raudio11. key signalaudio
Messor as envelope follower
Use Messor purely as an envelope follower — audio passes via Bypass, GR OUT modulates a filter elsewhere.
Walkthrough
  1. Flip Bypass switch ON (audio passes through unaffected).
  2. Set Threshold low, Ratio high, Attack ~10ms, Release ~150ms — drives GR OUT hard.
  3. Patch the percussion source → IN L.
  4. Patch GR OUT → external filter cutoff CV (or any CV destination).
  5. Adjust Threshold so GR OUT swings on every drum hit.
Signal out GR OUT — gain-reduction envelope as CV. Patch into filter cutoff, VCA CV, or anywhere you want drum dynamics to modulate.
Listen for The external filter (or destination) pulses in lockstep with the drum loop — ducking on each hit, recovering at the release rate.
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 2 connections. Modules: Messor, Filter, Drums. Signals: 1 audio, 1 cv.MessorFilterDrumsBypass: ONAttack: ~10msRelease: ~150msRatio: heavyIN LaudioGR OUTcvCutoffcvOutaudio11. drum envelope modulates pad filteraudiocv
Transient inverter
Push Ratio past limiting into negative territory so a snare's attack becomes quieter than its tail — a reversed-snare effect.
Walkthrough
  1. Turn Ratio fully clockwise (into over-compression / negative ratios).
  2. Set Attack medium (~30ms) so the initial transient gets through before the envelope clamps.
  3. Set Release ~100ms, Threshold low so most of the signal sits above it.
  4. Patch snare → IN L.
  5. Take OUT L to your output and listen for the inverted shape.
Signal out OUT L — snare audio with inverted dynamics: attack quieter than tail.
Listen for The snare's crack is squashed flat while the tail swells back up — a backwards/swelling shape, not a normal hit.
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 2 connections. Modules: Messor, Snare, Output. Signals: 2 audio.MessorSnareOutputRatio: full CW (over-compression)Attack: ~30msRelease: ~100msThreshold: lowIN LaudioOUT LaudioOutaudioInaudioaudio
Clean stereo VCA
Bypass the compressor and use Messor as a clean CV-controlled stereo VCA via the Gain CV input.
Walkthrough
  1. Turn Gain fully CCW (mutes the output until GAIN CV opens it).
  2. Turn Ratio fully CCW (compressor off).
  3. Leave Bypass off.
  4. Patch a stereo source → IN L / IN R.
  5. Patch an envelope (or LFO) → GAIN CV.
  6. Take OUT L / OUT R.
Signal out OUT L / OUT R — stereo audio amplitude-modulated by GAIN CV. Acts as a clean stereo VCA.
Listen for Audio is silent at rest; each envelope rise opens both channels in lockstep — like a normal VCA but stereo, with Messor's clean signal path.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 5 connections. Modules: Messor, Envelope, Pad, Output. Signals: 4 audio, 1 cv.MessorEnvelopePadOutputGain: full CCWRatio: OFFBypass: OFFIN LaudioIN RaudioGAIN CVcvOUT LaudioOUT RaudioOutcvOut LaudioOut RaudioIn LaudioIn Raudio11. opens stereo VCAaudiocv
Pumping sidechain filter sweep
Modulate the sidechain filter cutoff with an LFO so different frequency bands trigger compression over time.
Walkthrough
  1. Set Filter switch to HP, Filter Cutoff to noon as a starting point.
  2. Set Ratio moderate (~3:1), Attack fast, Release ~150ms.
  3. Patch a pad → IN L.
  4. Patch a slow LFO → FLT CV (start with low depth via the LFO's level).
  5. Set Threshold so the pad ducks intermittently as the cutoff sweeps.
  6. Take OUT L.
Signal out OUT L — pad audio with shifting, sweep-driven ducking.
Listen for The pad ducks and recovers at uneven intervals as the LFO opens the sidechain to different parts of the spectrum — rhythmic but not strictly tempo-locked.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 3 connections. Modules: Messor, LFO, Pad, Output. Signals: 2 audio, 1 cv.MessorLFOPadOutputFilter: HPRatio: moderateAttack: fastIN LaudioFLT CVcvOUT LaudioOutcvOut LaudioInaudio11. sweeping sidechainaudiocv
★ Drum-bus glue
Gentle stereo bus compression with Warm engaged — cohere a drum submix without obvious pumping.
Walkthrough
  1. Engage the Warm switch.
  2. Set Ratio ~2:1 (just past unity), Attack medium (~10ms), Release fast.
  3. Set Threshold so the LED ring shows 2–4 dB of gain reduction on peaks (light touch).
  4. Patch drum submix L/R → IN L / IN R.
  5. Take OUT L / OUT R.
Signal out OUT L / OUT R — drum submix, glued and saturated. Patch into the master bus.
Listen for Drums sit tighter together with subtle harmonic thickness from Warm; transients are softened, not crushed.
▸ Show diagram
Patch diagramPatch diagram with 3 modules and 4 connections. Modules: Messor, Mixer, Output. Signals: 4 audio.MessorMixerOutputWarm: ONRatio: 2:1Attack: mediumRelease: fastThreshold: light touchIN LaudioIN RaudioOUT LaudioOUT RaudioOut LaudioOut RaudioIn LaudioIn Raudioaudio
Rhythmic clock-driven ducking
Use a clock through an AD envelope as an audio-rate key signal to duck a pad on every tick.
Walkthrough
  1. Patch a clock → AD envelope trigger.
  2. Set the AD short (a few ms attack, ~50ms decay) so it produces a percussive pulse.
  3. Set Messor: Filter HP, Cutoff ~200Hz (so the bass of the pulse doesn't pre-trigger), Attack fast, Release ~300ms, Ratio heavy.
  4. Patch AD output → SC IN (acts as the key signal).
  5. Patch pad → IN L.
  6. Set Threshold so each clock tick produces a clean duck. Take OUT L.
Signal out OUT L — pad audio ducked on every clock tick.
Listen for The pad pumps in time with the clock — tighter and more controllable than using a raw kick because the AD shapes the key pulse.
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 4 connections. Modules: Messor, Clock, AD, Pad, Output. Signals: 3 audio, 1 trigger.MessorClockADPadOutputFilter: HPRatio: heavyAttack: fastRelease: ~300msSC INaudioIN LaudioOUT LaudioOuttrigTrigtrigOutaudioOut LaudioInaudio11. audio-shaped keyaudiotrigger
★ Parallel NY drum squash
Crush a drum loop in parallel with Warm engaged, then blend with the dry signal at a mixer for an aggressive NYC-style bus.
Walkthrough
  1. Mult the drum loop into two paths.
  2. Send path 1 dry → mixer channel 1.
  3. Send path 2 → IN L. Set Messor: Ratio past limiting, Warm ON, Attack fast, Release fast, Threshold low.
  4. Patch Messor OUT L → mixer channel 2 (the crushed parallel signal).
  5. Blend: start with mostly dry, then push the crushed channel up until it adds body and grit without dominating.
  6. Take the mixer output.
Signal out Mixer output — dry drums plus a parallel layer of squashed, saturated drums.
Listen for The dry transients stay sharp, while the parallel crushed layer fills in sustain and saturation — drums become bigger, denser, and more aggressive without losing punch.
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 5 connections. Modules: Messor, Mult, Mixer, Drums, Output. Signals: 5 audio.MessorMultMixerDrumsOutputRatio: past limitingWarm: ONAttack: fastRelease: fastIN LaudioOUT LaudioInaudioOut 1audioOut 2audioIn 1audioIn 2audioOutaudioOutaudioInaudio121. dry2. crushedaudio

Behaviors

Over-compression / negative ratios Ratio past limiting (full CW)

Past infinite ratio, signals above threshold are reduced below threshold — loud sections become quieter than quiet ones. Reshapes drum transients into reversed-attack or synthetic pumping shapes.

Sidechain filter as key-EQ HP/LP switch + Cutoff

Filtering the detection path lets specific frequency bands trigger compression. HP at ~200Hz ignores bass so kick/bass don't over-trigger. LP isolates lows for classic kick-driven ducking.

Stereo VCA mode Gain knob fully CCW + CV at GAIN CV

With makeup at zero, GAIN CV opens the output VCA directly. Messor becomes a clean stereo VCA — compression optional.

External sidechain key Cable in SC IN

Patching SC IN disconnects the internal detection path. Classic kick-to-bass ducking, or feed a hi-hat to compress a pad on every tick.

Gain-reduction envelope as modulation GR OUT patched to any CV destination

GR OUT emits the compression envelope as usable CV. Patch into filter cutoff or VCA CV to duck other voices in lockstep, or use Messor purely as an envelope follower (Bypass on).

Warm saturation Warm switch engaged

Adds progressive tube-style soft-clipping. Subtle on quiet signals, thickens as levels rise. Stacks with heavy compression to glue a full mix or drum bus.

Controls

Global Threshold Sets the level above which compression engages. LED ring indicates when signal crosses threshold and shows gain-reduction amount.
LED ring feedback · illuminates when signal exceeds threshold
Global Ratio Compression ratio. Sweeps from off through normal ratios into limiting and past unity into negative/over-compression where signals above threshold are pushed below it.
CCW: off · mid: 1:1 to ∞:1 · CW: negative ratios (over-compression)
Global Attack Gain-reduction envelope rise time. Fast settings catch transients, slow settings let initial peaks punch through.
1ms – 500ms · CV controllable
Global Release Gain-reduction envelope fall time. Short for pumping, long for smoother levelling.
5ms – 3.5s · CV controllable
Global Gain Makeup gain post-compression. Full CCW mutes the output, turning the stage into a CV-controlled stereo VCA via Gain CV.
CCW: mute / VCA mode · CV controllable
Sidechain Filter Cutoff Cutoff for the sidechain filter that shapes what triggers compression. Lets kick/bass duck more or less depending on mode.
10Hz – 9kHz · CV controllable · pairs with HP/LP mode switch
Sidechain Filter Mode Switch Selects sidechain filter response. HP ignores low end (vocal/drum glue), LP ignores highs (kick-focused ducking).
HP / LP toggle
Global Warm Switch Engages analog tube-emulation soft-clipping saturation on the output path. Adds harmonic thickness and progressive compression.
Pure / Warm toggle
Global Bypass Switch Routes input directly to output, skipping compressor and Warm stage for A/B comparison or for using Messor purely as an envelope follower via GR OUT.
Bypass / Active toggle

I/O

IN · 6

  • IN L / IN R AUDIO
    Stereo audio input. Mono sources can patch either jack.
  • SC IN
    External sidechain input. Overrides the internal sidechain path — use for classic kick-ducks-bass patches.
  • ATK CV CV
    CV over attack time.
  • REL CV CV
    CV over release time.
  • FLT CV CV
    CV over sidechain filter cutoff.
  • GAIN CV CV
    CV over makeup gain. With Gain knob fully CCW, becomes the CV input of a clean stereo VCA.

OUT · 2

  • OUT L / OUT R AUDIO
    Stereo compressed (or bypassed) audio output.
  • GR OUT ENV
    Gain-reduction envelope as CV. Mirrors the internal ducking curve for driving other VCAs, filters, or for using Messor as a standalone envelope follower.