# Background music

The optional background music of the demos (toggle ♪ in the top bar) plays
seven calm piano pieces: three by Erik Satie (1866-1925) in public-domain
recordings, and four by Kevin MacLeod under the Creative Commons Attribution
4.0 license. All of them can be redistributed with this project; the four
CC BY pieces require the attribution given below.

## Public domain

The compositions and the recordings are in the public domain, so they can be
redistributed without restriction.

| File | Piece | Performer | Source | License |
|---|---|---|---|---|
| `gymnopedie1.mp3` | Gymnopédie No. 1 (*Lent et douloureux*) | Robin Alciatore (Musopen) | [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Erik_Satie_-_gymnopedies_-_la_1_ere._lent_et_douloureux.ogg) | Public domain (released by the performer) |
| `gnossienne1.mp3` | Gnossienne No. 1 | La Pianista | [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Satie_-_Gnossienne_1.ogg) | Public domain |
| `gnossienne3.mp3` | Gnossienne No. 3 | La Pianista | [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Gnossienne_3_(Satie).ogg) | Public domain |

## Creative Commons Attribution 4.0

| File | Attribution |
|---|---|
| `meditation-impromptu-01.mp3` | "Meditation Impromptu 01" Kevin MacLeod ([incompetech.com](https://incompetech.com)). Licensed under Creative Commons: By Attribution 4.0, <https://creativecommons.org/licenses/by/4.0/> |
| `meditation-impromptu-02.mp3` | "Meditation Impromptu 02" Kevin MacLeod ([incompetech.com](https://incompetech.com)). Licensed under Creative Commons: By Attribution 4.0, <https://creativecommons.org/licenses/by/4.0/> |
| `clean-soul.mp3` | "Clean Soul" Kevin MacLeod ([incompetech.com](https://incompetech.com)). Licensed under Creative Commons: By Attribution 4.0, <https://creativecommons.org/licenses/by/4.0/> |
| `light-thought-1.mp3` | "Light Thought var 1" Kevin MacLeod ([incompetech.com](https://incompetech.com)). Licensed under Creative Commons: By Attribution 4.0, <https://creativecommons.org/licenses/by/4.0/> |

The originals were downloaded from incompetech.com in October 2026.

## Changes

All files were re-encoded to 96 kbit/s stereo MP3 with loudness normalization
(about -22 LUFS) and short fades, so that the pieces play at a similar, quiet
level and work in every browser. The Satie recordings were converted from the
original Ogg Vorbis files; the Kevin MacLeod pieces from the original MP3
files, otherwise unchanged.