Made by Granary Digital, www.granary.digital. Free to use. 48 kHz, 24-bit mono WAV. Levels are RMS: a -18 dBFS sine peaks at -15 dBFS.

tone: line-up level for setting gain on every channel.
pink noise: check each mic channel and speaker sounds the same.
sync clap: a 10 ms 1 kHz blip every 2 s from 1 s, for lining up separate recorders in the edit.
