In-House Instrument · v1.8.0

Composure

A sonic sketchbook with a
collaborator built in.

Composure is a music app you carry in your pocket and a bandmate that plays alongside you at the desk. Catch the idea where it happens — play it, hum it, tap it, draw it — then bring it home and let an agent pick up the instrument with you.

Meet the Instrument Read the Dispatch
Composure running: the Synth Forge panel open on a Velvet Pad patch.
The running app — every image on this page is a capture from the live build. No mockups, no renders.

Two Ways to Play It

A composer’s notebook on the go.
An agentic collaborator in the studio.

Same engine, two jobs. It helps to say them apart.

On Android

A Sonic Sketchbook

Catch the idea where it happens. Hum a line and it becomes notes on the spot — no cable, no setup, nothing uploaded. Or plug in and play — pads, drum pads, a MIDI keyboard — and it takes the notes straight into the session.

  • —Runs on its own, anywhere.
  • —Or becomes the controller for the instrument on your desk.
  • —Same sessions on both ends — an idea caught on the bus is waiting when you sit down.
Composure's Sketch room on Android.

Desktop + Android

An Agentic Collaborator

The part that's new. An agent that doesn't just talk about your music — it plays it, and it can change what's playing while it plays.

  • —Ask for a change, hear it in the performance.
  • —Change one voice; the other fifteen hold.
  • —Reaches your gear — a real instrument inside your DAW.
Composure's Record room on desktop.
16
Channels, one instrument
2
Agents that play them
14
Rooms to work in
1
Sketchbook, phone to desk

The Collaborator

An agent in the band.
Two ways in.

Most AI music tools hand you back a file. Composure's agent reaches the engine itself, so a request lands on the live performance — transpose the bass, drop the drums, build a patch, shift the mood. Everything else keeps playing.

Composure's Brainstorm room with the agent panel open.
The agent, in the app — describe the idea in words and it exists.

In the app

Ask it to play, sketch, or change what's playing. It happens in the window in front of you.

Outside the app

Flip one switch and Substrate sees Composure as a connected instrument and drives it from there.

Dungeon Master

Give it a brief — a progression, a difficulty, a skill to practice. It turns practice into a scene.

Brainstorm

Describe the idea in words and it exists — a part, a kit, a patch. The prompt is the sketch.

“An agent that can only read the song is an assistant. One that can change a single voice without disturbing the others is a bandmate.”

In Your DAW

It shows up in your DAW
like any other instrument.

Play from the app, hear it through the sounds you already use — Ableton, Logic, FL Studio, Maschine, any of them.

  • —In time, either way — it can set the tempo, or follow yours.
  • —Follows your hands — sustain, and touch that bends as you move.
  • —Your keyboard, remembered — plug it in once and it's there next time.
Composure's Timeline room.

Notation

Play it or hum it.
Get sheet music.

Switch to Composer and what you played is written out as real notation — key signatures, tied notes, treble and bass — not a piano roll. Export it as a clean image for a chart or a lead sheet, dark or light.

Composure's Composer room, showing engraved notation.
Composer — what you played, written out as real notation.

Sound

Every sound can
become an instrument.

Four short doors into the same engine. Take whichever one is closest to the idea in your head.

Hum it in

Sing or hum a line and it becomes notes you can edit, right on the device. Offline — nothing leaves the machine.

Record it

Grab a sound from the mic or from your computer, trim it, and build a playable instrument around it.

Describe it

Tell the agent the sound you want and it builds the patch.

Generate it

Soundscapes writes ambient music straight onto your channels. Pick a mood, the whole band answers, and point any part at any voice you like.

Warm Dark Mystic Deep Calm Sad Tense Sweet Cinematic Ethereal Cosmic Meditative Joy Dreamlike
Composure's Soundscapes room.
Composure's Synth Forge room.

Synth Forge is a full workbench — oscillators, filters, envelopes — and it draws the sound as standing-wave patterns while you tune.

Radio is a map of stations with a live 3D view, and it can generate music as it plays, steered by a word from you.

Composure's Drum Forge room on Android.

Pocket and Desk

In your pocket,
on your desk.

The Android build is the full instrument, not a viewer.

  • —Standalone — the whole thing runs on the phone or tablet.
  • —Controller — on the same network it plays the desktop, so the tablet on your stand is an input surface for the instrument at the desk.
  • —Feels like playing — pads and keys answer with a tap back.

Get Composure

One instrument.
Pick your build.

One-time purchase, yours to keep. Both builds are the full instrument — take the one that matches the machine in front of you, or both.

Pocket

Android

$12

The full instrument on the phone or tablet — standalone, or a controller for the desk.

  • Direct-install APK · 13 MB
  • Sixteen channels, every room
  • Plays the desktop over your network
Buy for Android

Desk

Windows

$16

The instrument at the desk, with the agentic collaborator and the virtual MIDI port.

  • NSIS installer · 204 MB
  • Per-user install, no admin required
  • Virtual MIDI out & clock for your DAW
Buy for Windows

Both

Pocket & Desk

$22.44 $28

The whole thing, on every machine you own — $5.56 less than buying the two apart.

  • Windows installer + Android APK
  • Both builds, one purchase
  • The same links for every future build
Buy both

Paid by card through Stripe. Your download links appear the moment payment clears — sign in to reach them any time.

The Rooms

You’ve seen eight.
Here’s the whole map.

One line each — the captures worth showing are up the page. Everything you make is one session, kept in one searchable place and drawn as a map you can walk, so an old idea can find a new one.

Dungeon Master

Practice as a scene — a progression, a difficulty, a skill.

Knowledge Graph

The archive, drawn as a map you can walk.

Settings

Where the instrument is wired up.

Radio

A map of stations, with music generated as it plays.

Timeline

The session, laid out over time.

Record

Capture a take, then build a playable instrument around it.

Sketch

Every stroke is a melody line.

Brainstorm

Describe an idea, and it exists.

Synth Forge

Oscillators, filters, envelopes — drawn as standing waves.

Drum Forge

Analog-style drums, plus a sample engine.

Soundscapes

Ambient music written straight onto your channels.

Composer

What you played, engraved as real notation.

One instrument.
Two players.

Built in-house at Propagation House — sixteen channels on one virtual instrument, playable by hand or by an agent, on Android and desktop.

Get Composure Read the Full Dispatch Back to the Studio