Grand piano recordings: Salamander Grand Piano by Alexander Holm.
License: Creative Commons Attribution 3.0 (CC BY 3.0).
https://creativecommons.org/licenses/by/3.0/
Sample distribution: https://tonejs.github.io/audio/salamander/
Original instrument: Yamaha C5 grand piano.
Samples are used for playback and transposed to cover the full keyboard.