Composer Assistant

Legal

Client work, AI and training data

Can you deliver it to clients? Independent MIDI: yes, like a licensed MIDI pack. Audio: for sketches and mockups unless your client agrees. Plus how the AI works and what it learned from.

Last updated 2026-09-29

Version 1.0 · Last updated 29 September 2026 · Powered by Stability AI

Can I use it in client work?

Yes. Composer Assistant gives you three kinds of take, and each has its place:

What you get Sketches, mockups, demos Your own releases Finished client work
Independent MIDI Yes Yes Yes — like a licensed MIDI pack
Audio takes Yes Yes Only if your client agrees in writing
MIDI of the audio Yes Yes Only if your client agrees in writing

So you get both: fast mockups from the audio, and finished work from the Independent MIDI.

In plain English

How Composer Assistant uses AI

Part What it does Is it AI?
Instrument models (chords, motors, ostinatos, percussion) Generate the audio takes from your idea and settings Yes. Stability AI's Stable Audio 3 Medium as the audio engine, plus layers we trained on our own music, one set per instrument
MIDI of the audio Reads the notes back from a generated take Yes. A small model we trained
Independent MIDI Writes MIDI from your settings No. A rule-based engine working from Cinematic Composing's MIDI packs
Input analysis Reads the notes, pitch and rhythm of audio you drop in or record Yes. Published transcription models by others (listed on our Third-party notices page); we didn't train them

All of it runs on our servers. Nothing AI runs on your computer. In Advanced, Style/Color sets how much of the character we trained is applied (1.0 = as trained).

Training data documentation

This section is our training-data documentation under California's AB 2013 (California Civil Code §3111). It covers the models Composer Assistant uses to make your takes. We update it before we release a new or retrained model.

Models covered

Model Trained Available to the public
Chords June–July 2026 17 September 2026
Motors July 2026 17 September 2026
Ostinatos July 2026 17 September 2026
Percussion July 2026 17 September 2026
MIDI of the audio (the MIDI reader) September 2026 27 September 2026

1. Sources and owners of the data

2. How the data serves the purpose

The MIDI packs give each instrument family its notes, rhythms and phrasing. The rendered audio teaches each model how that music sounds played by an orchestra. The MIDI paired with each clip teaches the MIDI reader to read notes back from audio. The descriptions and musical labels let the model follow your settings.

3. How much data

Model Training clips
Chords 10,000–20,000
Motors 20,000–30,000
Ostinatos 5,000–10,000
Percussion 1,000–5,000
MIDI reader 30,000–40,000 (the same clips as the instrument models)
Stability AI's base model 1,278,902 recordings (per its model card)

4. What the data looks like

Stereo audio clips, 44.1 kHz, 24-bit, from about 4 to 40 seconds long. Each clip comes with its MIDI, a text description and musical labels: instrument, articulation, mood, key and mode, chord names, tempo, time signature, register and layer.

The compositions and sound recordings in our data are protected by copyright. They're owned by Cinematic Composing or used under license. They are not in the public domain. No material protected by trademark or patent was intentionally included. For the base model, Stability AI states that its data is licensed or under Creative Commons licenses, and that identified copyrighted music was removed from the Freesound portion.

6. Purchased or licensed

The MIDI packs and the rendered audio are Cinematic Composing's own. The recordings behind our sample libraries are licensed for AI training or come from our own sessions. We bought no datasets. For the base model, Stability AI licensed its data from AudioSparx and used Creative Commons audio from Freesound.

7. Personal information

To our knowledge, none. The data is instrument recordings, MIDI and musical labels — no voices, no names, no customer data.

8. Aggregate consumer information

None.

9. Cleaning and processing

10. When the data was collected

The audio was rendered between 24 June and 22 July 2026, from MIDI packs composed earlier for Cinematic Composing. Collection isn't ongoing. When we add instruments, we'll add data and update this page before release.

11. When the data was first used

The chords data was first used in June 2026. The motors, ostinatos and percussion data were first used in June–July 2026. The MIDI reader's training in September 2026 reused the same clips.

12. Synthetic data

Yes, in this sense: all our training audio was rendered from MIDI through sample libraries, rather than recorded live for these compositions. The key and tempo variations were made by re-rendering, and the text descriptions were generated by templates. No audio made by other AI models was used.

Your data and our training

We never use your files, recordings, MIDI captured from your DAW, descriptions, the notes, chords and tempo we read from them, or your takes to train any AI model — ours or anyone else's — and we never sell or license them for AI training. The training we do uses only music written by professional composers and carefully curated for it — a slow, deliberate process. Training on anyone's music would first need their permission, and we have never asked for it. If that ever changed, we would ask your permission first, through a separate opt-in that is off by default. This promise is part of our Terms of use, and anyone who takes over Composer Assistant must keep it.

AI-generated output and the EU AI Act

Questions

Write to hi@cinematiccomposing.com. Composer Assistant is made by Cinematic Composing LLC, Lake Forest, California, USA.