Salamander Grand Piano V3 by Alexander Holm
Licensed under Creative Commons Attribution 3.0 Unported:
https://creativecommons.org/licenses/by/3.0/

Source: https://github.com/sfzinstruments/SalamanderGrandPiano
Changes: a subset of 5 velocity layers (v2, v6, v9, v12, v15) and the
range A1-C6, leading silence removed, trimmed to 5 seconds with a fade-out,
encoded as 128 kbps MP3 (scripts/build-piano-samples.mjs).

The ImproMIX guides use 3 of these layers (v6, v9, v12).