Music AI that actually knows theory.

KORUS

Sing one line and hear it answered in five parts, in your own voice, with your formants intact. It voices against the chart, so the harmony moves when the chord does. A browser and a microphone, nothing to install.

Helix Arpeggiator

Voice-led paths across your changes. Every note is legal against the chord underneath, and every performance is reproducible from a seed and a tempo, so you can keep the take you liked.

Conductor

Describe the feel in words. THIRI arranges a four-piece band with harmony, bass and drums, then plays it in the browser. The theory is decided before a note is rendered.

Studio Rack

Helix, Vocal, Keys, Drums and Band in one page, each wired to the live API. The closest thing to seeing the whole engine at once.

Sound Corpus 3D

155 sound samples mapped across Pitch (X), Timbre (Y), and Envelope (Z) in Euclidean space. Grounded by THIRI's deterministic theory engine so an AI agent can query sound with mathematical certainty.

Three parts, one instrument.

THIRI decides the notes. It never synthesises: each harmony voice is your own sound moved onto its calculated note, formants kept, so the section is still you.

Elk Audio supplies the hardware. Their Stomp runs a headless audio OS, which is what lets the whole engine sit inside a 1.333 ms callback with no computer in the room.

MUTEK and Music Hackspace are where it was built and judged. Two days in Montreal, August 2026: first in the Elk Audio challenge, second in Roland Project LYDIA.

The VST and the standalone

A plugin for your DAW and an app that runs on its own. Five voices of formant-preserving harmony off a live horn, voiced against the chart rather than a fixed interval. This is the build that won the challenge, running in Ableton.

The stomp pedal

The same engine, headless on a stock $399 Elk Stomp. No laptop, no network, no second box. Five voices at 0.82 ms average and 1.11 ms worst against a 1.333 ms deadline, zero dropouts across three sweeps.

The pedal is a measurement instrument first. You cannot buy it. What it has not had is players: everything measured so far was measured by the person who built it, on one board, with one horn.

Composer C

Sketch a progression, reharmonise it, hear it voiced properly, and keep the result, because it will be the same result tomorrow. Form, harmony, layers and stems from one spec you can carry on editing.

Run the Changes

A practice tool that holds you to the chart. It generates the changes, voices them correctly, and keeps the harmony honest while you play over it, so what you hear in the room is what the tune actually does.

FYLLM

Drop in an AI video and get a score that follows the cut, rendered on your own Mac with the same harmony engine underneath. Nothing leaves your machine. Licences from $47.