# Formula engine audio credits

The playground uses `renault-v10.wav` from the Speed Dreams data repository,
distributed here as [`v10-race.wav`](v10-race.wav). The file is unchanged apart
from its name.

## Source and attribution

- Project: Speed Dreams, with contributions inherited from TORCS.
- Source revision: `5ee49962064902d70cb702952d567ffccebf752c`.
- [Original WAV at that revision](https://forge.a-lec.org/speed-dreams/speed-dreams-data/raw/commit/5ee49962064902d70cb702952d567ffccebf752c/data/data/sound/renault-v10.wav).
- [Project credits at that revision](https://forge.a-lec.org/speed-dreams/speed-dreams-data/raw/commit/5ee49962064902d70cb702952d567ffccebf752c/data/data/credits.xml).
- [Repository licensing statement at that revision](https://forge.a-lec.org/speed-dreams/speed-dreams-data/raw/commit/5ee49962064902d70cb702952d567ffccebf752c/README.md).

Credit to the Speed Dreams and TORCS contributors. The project credits also name
Jan Ullmann (audioberlin) for general sound work, describing his rework as covering
most sound samples except most car-specific ones. They do not identify the
recorder or editor of this particular file.

## Licence and downloads

The recording is distributed under the Free Art License 1.3. The repository
licenses non-functional data under the Free Art License by default; the sound
directory's listed exceptions do not identify `renault-v10.wav`.

- [Download the unchanged recording](v10-race.wav).
- [Download the bundled Free Art License 1.3 text, in French](free-art-license-1.3.txt).
- [Read the Free Art License 1.3 in English](https://artlibre.org/licence/lal/en/).

The WAV is 373,422 bytes. Its SHA-256 is
`bb2b98459231bc4825cc994af9ac521ea3400fe048e3133f82be0f69c2483edf`.

## Playback changes and limits

The browser loops the sample and adapts its pitch, filters and gain to the
playground's RPM, throttle, engine load and gear changes. Parallel intake and
overrun filters, presence equalisation and compression shape playback. These
runtime effects do not change the distributed WAV.

The original recording vehicle and native RPM are unspecified. The filename
does not establish a recording of a particular Formula 1 car. The playground
uses an inferred 6,120 RPM pitch anchor, based on an approximately 510 Hz firing
component interpreted as a four-stroke V10. It is a playback-tuning assumption,
not published recording metadata or a calibrated acoustic model.

## Retired recordings

The `engine-loop-0.wav` through `engine-loop-5.wav` files remain in this directory
but are unused. They are by domasx2, from
[OpenGameArt's racing car engine sound loops](https://opengameart.org/content/racing-car-engine-sound-loops),
under Creative Commons CC0. Their source describes a generic car startup excerpt
and pitch-only variants. It does not identify a Formula 1 recording.