Variable: DEFAULT_BUSES
const DEFAULT_BUSES: readonly ["music", "sfx", "voice", "ambience", "ui"];
Defined in: audio.ts:33
The buses a director starts with, each at unity gain. Any other name works
too - a bus springs into existence at unity the first time it is named.
master is NOT in here: it is a separate scalar over all buses, so that
"duck everything" and "turn the music down" never fight over one number.