Voice limiting
Also said as Polyphony limit, Voice stealing, Virtual voices, Max instances
A cap on how many sounds can play at once. When a new sound needs a voice past the limit, the least important one is stopped: it is stolen.
Without a cap, a hundred coins at once sum into distortion and waste processing on sounds nobody can pick out. With priorities, the important ones always get through.
Say it
“Limit coin pickups to 8 voices, and steal the oldest first. Dialogue and the player's own shots have top priority and are never stolen.”
Where you’ve seen it
On the NES, a sound effect takes over one of the music's channels while it plays, so the tune loses a part for a moment. Battlefield: Bad Company culls sounds by loudness, so anything drowned out by a louder one is not processed at all.
Not to be confused with mix
A mix sets how loud each sound is. Voice limiting decides which sounds get to exist at all.