A free harmonic composition workstation where every note is defined by its relationship. Use it standalone or inside your DAW — then upgrade to DonutStudio Pro for sampling, vocals, and audio transformation.
Binary downloads are temporarily unavailable. All previous downloadable versions have been withdrawn while the video helper's dependencies are replaced. Downloads will return after a new build is ready.
See the DonutStudio website for updates.
Every other piano roll treats notes as fixed grid positions, each locked to one frequency. DonutStudio treats notes as relationships.
- Every note's frequency comes from its link chain — pure ratios from the harmonic series, any interval, any harmonic.
- Harmonic context is the note — move a master note and everything linked to it follows.
- Linking is the tuning — one automatic system, not manual per-note microtuning.
- 12-TET is just the starting point — just intonation, EDO, and arbitrary ratios are all first-class.
Compose
- Harmonic piano roll with just-intonation link chains
- JI-aware chord detection, auto-link from chords, progression-aware retuning
- 30+ note transforms — quantize, humanize, retrograde, and more
- Clip arranger with audio + MIDI clips, automation lanes, and tempo maps
Sound
- Sybil-16 virtual-analog synth and OP-7 FM synth (20,800+ presets)
- SF2 / SFZ soundfonts — 1,300+ instruments, GM-compatible, microtonal playback
- 480+ Airwindows effects plus Donut Devices clean utility effects
- In-app store for instruments and content
Produce
- A full standalone DAW — clip arranger, mixing, and stem export
- VST3 / CLAP plugin mode inside every major DAW
- MIDI import / export with microtuning preserved
The transformation and media tier:
- Per-note audio sampling and audio-to-note transcription
- Harmonic pitch correction and vocal resynthesis
- DiffSinger and UTAU vocals
- A beat-synced video editor with score-reactive visuals and a music → image modulation matrix
VST3 in Bitwig, Reaper, Ableton Live, FL Studio, Studio One, and Cubase; CLAP in Bitwig and Reaper. Or run it fully standalone — no DAW required.
See screenshots and demos at donutsdelivery.online/donutstudio.
DonutStudio is scriptable and agent-controllable. This repository holds the public developer resources:
docs/lua-scripting.md— Lua scripting overview and install locationdocs/api-reference.md— the publicarbitscripting API surfacedocs/skinning.md— skin format overview (preview)examples/— ready-to-edit scripts (transforms, generators, analysis) and skin packsskills/— agent skills for Claude Code, Cursor, and Codex
local notes = arbit.get_notes()
for _, note in ipairs(notes) do
if note.velocity < 40 then
arbit.set_note_velocity({ noteId = note.id, velocity = 80 })
end
endAI coding agents can drive DonutStudio directly through its MCP server or the port-9900 command server — import, beat-sync, effect, export, and then verify the result. See skills/README.md.
The video helper has been removed from the current repository tree while dependency replacement continues in private development. Previously published source remains in Git history at commit c1148eb and in existing source tags. Those versions retain their original licenses and third-party notices. Removing the current directory does not change those rights.
DonutStudio is closed source — built by one person, in Denmark. This repository contains documentation, examples, integration resources, and historical release records. Binary downloads are currently withdrawn. It does not contain the application source, build system, license server, DSP engines, or model integrations.
Documentation and example scripts in this repository are MIT licensed unless a file states otherwise. Previously published video-helper source retains the licenses recorded with each version. The DonutStudio application itself is proprietary; see the in-app EULA.