HIGHWAY DUEL AUDIO CREDITS

Engine source recordings / sound assets:
Generic V8 Engine Sound, DerMeehdrescher / Meehdrescher Studios
https://opengameart.org/content/generic-v8-engine-sound
Generic Flat 6 Engine Sound, DerMeehdrescher
https://opengameart.org/content/generic-flat-6-engine-sound
License: Creative Commons Attribution-ShareAlike 4.0 International.
https://creativecommons.org/licenses/by-sa/4.0/
Full license included in CC-BY-SA-4.0.txt.
Original supplied WAV files included in original-v8.zip and original-six.zip.

Adaptations by Highway Duel: whole-loop RPM banks at 1600, 3200 and 5600 RPM,
formant-preserving pitch adjustment with FFmpeg Rubber Band, level matching,
mono 44.1kHz PCM conversion, and short loop-boundary crossfades at playback.
The adapted v8_* and six_* WAV files are also licensed CC-BY-SA 4.0.
Source RPMs: V8 power 5570 / coast 5581, flat-six 5500.
These are two shared sound families, not recordings of five specific vehicles.
The source authors label these realistic engine sound assets; no claim of
verified manufacturer or microphone-recording provenance is made.

Road, wind, gravel, skid, shift, collision and pressurized air: generated
sound assets for this project. These are sound effects, not field recordings.
No synthesized noise or granular combustion layer is used for the engine.