A modular synthesizer in your browser, made of Faust modules.
No installation, no account: it runs in Chrome, Edge, Firefox or Safari (Chrome or Edge recommended).
Each module is a small Faust program: oscillators, filters, envelopes, sequencers, effects, reverbs, physical models… Connect them with cables, channel by channel, modulate any setting by any signal, and open the code of a module to change it, or write your own. Everything is compiled in the browser.
- First steps
- Modules
- Cables
- Modulation
- The interface of a module
- Writing your own modules
- Large patches
- Sound
- Scenes and files
- Keyboard and mouse
- More
The first time you open faustmodular, a sine oscillator is already connected to the speakers: press its gate button to hear it. The microphone (on the left) and the speakers (on the right) are modules too.
Then open the Modules menu, add a few modules, and connect them.
The Modules menu holds more than 200 modules, in families:
- Modular: the building blocks of a modular synthesizer (VCO, VCF, VCA, ADSR, LFO, Clock, Sequencer, Quantizer, Mixer, MIDI to CV…), with common conventions: audio in [-1, 1], pitch 0.1 per octave, gates 0/1;
- FaustPlayground: harps, winds, bars and bowls, instruments with reverb, filters, echoes…;
- Faust libraries: reverbs (Zita, JPverb, Greyhole…), compressors, the Moog filter, equalizers, guitar pedals, saturation, delays, drums, physical models (flute, violin, bells…), analyzers;
- My modules: the modules you wrote or changed.
Type to search: the field is ready as soon as the menu opens. ↑ ↓ choose a module (its description is shown on the right), Enter adds it. Double click or drag a module to add it too.
To play from a MIDI keyboard, add the MIDI to CV module (Chrome, Edge, Firefox): drop its pitch on the Pitch of a VCO and its gate on the Gate of an ADSR. It also gives the velocity, the modulation wheel and the aftertouch, and adds the pitch bend; one note at a time, on one channel or all. To play in time with a drum machine, a hardware sequencer or a DAW, the MIDI Clock module follows its MIDI clock: a gate per sixteenth note (or eighth, quarter, bar) for a Sequencer, a reset at Start, and the tempo it measures.
Each module has one port per channel: inputs in green on the left, outputs in coral on the right.
- Drag from a port to a port of the other kind to connect them, or onto the body of a module to connect all the channels at once (stereo to stereo, mono to both sides…).
- Click a cable to delete it.
- Click an output (without dragging) to send it to the speakers, or to unplug it, without drawing a cable across the whole patch.
Cables may form loops: a cable that closes a cycle is dashed, and delayed by a short buffer.
Drop a cable on a slider, a knob or a button instead of a port: the signal now drives that setting. A small round port appears on the left of the setting, with a sign for the way the signal acts on it (± around its value, + added, ~ frequency modulation, ⇐ drives it) and a ring for the depth: drag it vertically to change the depth.
The settings of a module are laid out as its Faust code describes them: groups, rows, tabs, sliders, knobs, buttons, checkboxes, menus and meters.
- Double click a value to type it.
- Drag a knob vertically (Shift: finer).
- Right click a module for its menu: copy, duplicate, minimize, unplug, delete…
The ◎ button of the title bar shows the settings of a module as an Orbit (faust-orbit-ui): each setting is a point around a centre, its value set by its distance to the centre; moving the centre moves them all, and random variations or presets are one click away.
The ✎ pencil of a module opens its code in faustcode, the Faust editor in the browser. Each time you save there (Ctrl/Cmd-S), the module is updated in place, with its settings, cables and modulations. A changed module is kept in My modules.
You can also:
- right click the stage and choose New module: an empty module, opened in faustcode to be written;
- open a program you edit in faustcode directly in faustmodular, with its faustmodular button;
- import a Faust file (.dsp) from the File menu, or drop it on the stage.
- Zoom with Ctrl/Cmd + the wheel (or a pinch), move with the wheel; ⤢ fits the whole patch in the window.
- Zoomed out, the module under the pointer is magnified to its real size: you can read and play it without zooming in. While you draw a cable, it lets you aim at a precise setting.
- Modules snap to the edges and centres of the others while you move them (Alt: no snapping).
- Drag a rectangle on the empty stage, or Shift-click, to select several modules.
- Undo anything with Ctrl/Cmd-Z.
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The speaker module sets the volume of the whole scene: drag it vertically, and its brightness shows the volume. Double click it to mute. A safety limiter protects your ears and speakers from a patch that runs wild (the speaker glows while it acts).
The microphone is only requested when you use it: when you connect a cable from it, or click it. It is closed when the last cable from it is removed, or by a click on it when no cable leaves it.
The transport of the toolbar (⏮, ▶ / ■, the tempo, bar:beat) drives a timeline shared by the Faust applications open in the browser (faust-sync): open faustmodular in two tabs, press ▶ in either, and both play; change the tempo in one, the other follows. The Sync Clock module (Modular library) turns that timeline into gates for a Sequencer: a gate per sixteenth note (or eighth, quarter, bar), aligned on the bar, a reset when the playing starts from the beginning, and run. On one sound card, the gates of the two tabs come out at the same sample: the position is counted in audio samples, not with timers (see the specification).
● Record, in the transport, records what you hear (the output, after the volume) into a FLAC file (24 bits,
lossless; or WAV): until you stop it, or a number of bars, always from the start of a bar, to the sample. With the
transport stopped, it starts it. The file is downloaded, named after the scene and the time; File ▸ Publish the
scene and its recording puts both in your store, in one commit, the recording linked to the scene it came from.
From a recording of a store (File ▸ Open from a store ▸ Recordings, or a link ?recording=), Open its scene
gives back the scene exactly as it was recorded, to make variants (see
recipes and materials).
Your scene is saved in the browser as you work, and opened again at your next visit. The File menu works as
in a desktop application: new scene, open, save (Ctrl/Cmd-S writes the same file again in Chrome and Edge), save
as, recent scenes and examples. Scenes are .jfaust files.
A store is a GitHub repository of Faust modules and scenes, with a simple layout (fauststore.json,
modules/<Name>/<Name>.dsp, scenes/<Name>/<Name>.jfaust; a model in templates/fauststore,
the specification in Documentation/STORE-SPEC.md). A public store is read without an
account:
- in the Modules menu, Stores, Add a store…: type
owner/repository. Its modules are in the library, found by the search, added like the others; its scenes are in File ▸ Open from a store; - a link opens a scene of a store as a new scene: put the address of its file on GitHub after
?scene=,https://orlarey.github.io/faustmodular/?scene=https://github.com/<owner>/<repository>/blob/main/scenes/<Name>/<Name>.jfaust(or?store=<owner>/<repository>&scene=scenes/<Name>/<Name>.jfaust).
Each store shows whether it is in read only or in write. Publishing to a store: click its read indicator, Write to this store…, and give it a token made on GitHub (a fine-grained token, for that repository only, with the permission Contents read and write; it stays in your browser and is only sent to GitHub). Then File ▸ Publish the scene to my store, or Publish to my store in the context menu of a module (a submenu when several stores are in write): one commit each, and the link to share the scene, at that version, is copied. A scene is published with its modules (those not already public: the library of faustmodular, or already in the store), so that faustcode can open them; a name taken by another code asks what to do.
| Add a module | Modules menu: type, ↑ ↓, Enter; or double click, drag |
| Connect | drag from a port to a port, or onto a module |
| Modulate a setting | drag from an output onto the setting |
| To the speakers | click an output |
| Delete a cable | click it |
| Type a value | double click it |
| Depth of a modulation | drag its port vertically (Shift: finer; double click: default) |
| Volume / mute | drag the speaker vertically / double click it |
| Zoom / move | Ctrl/Cmd + wheel, pinch / wheel |
| Select | rectangle on the stage, Shift-click |
| Move without snapping | Alt while dragging |
| Undo / redo | Ctrl/Cmd-Z / Ctrl/Cmd-Shift-Z |
| Copy, cut, paste, duplicate | Ctrl/Cmd-C, X, V, D |
| Delete the selection | Delete |
| Save / save as / open | Ctrl/Cmd-S / Ctrl/Cmd-Shift-S / Ctrl/Cmd-O |
- The reference manual: every feature in detail, and the development notes
(
npm install,npm run dev,npm test). - The modular library and its conventions.
- What changed: the changelog.
- The Faust language: faust.grame.fr, and its documentation.
faustmodular was born as an extension of FaustPlayground, a Web platform designed by GRAME to teach audio programming to children. It is written by Yann Orlarey: the λ seal in the corner of the application leads here.
The screenshots of this page are made by npm run screenshots.