# Bach Inventions — sources and licenses

Johann Sebastian Bach's Two-Part Inventions, BWV 772–786, are public-domain compositions. These MIDI files and accompanying LilyPond sources were downloaded unchanged from the Mutopia Project on 2026-09-12. They are score-based computer performances, not recordings by a pianist.

Collection: https://www.mutopiaproject.org/cgibin/make-table.cgi?collection=bachis

| Inventions | Editor / maintainer | Edition license |
| --- | --- | --- |
| 1, 6, 9, 12 | jeff covey | Creative Commons Attribution-ShareAlike 3.0 |
| 2–5, 7–8, 10–11, 13–15 | Allen Garvin | Public Domain |

All editions identify Bach-Gesellschaft as their source. Original headers, copyright notices, and maintainer credits are preserved in `sources/*.ly`. Individual original URLs are recorded in `sources/manifest.json`. No notes or timing in the distributed MIDI files have been edited. The app replays their notes with Grand Piano samples and the user's selected tuning and playback speed.

CC BY-SA 3.0: https://creativecommons.org/licenses/by-sa/3.0/

Grand Piano samples: tonejs-instruments by nbrosowsky, licensed Creative Commons Attribution 3.0. These are the site's existing sample files under `/audio/grand-piano/`.

- https://github.com/nbrosowsky/tonejs-instruments
- https://creativecommons.org/licenses/by/3.0/

The polygon drawings are an artistic encoding of notes and ideal harmonic numbers. They are not recordings or predictions of physical cymatics.