An ensemble of snoring individuals, within the same room.
"Oh snap bro, did you hear Erick and Donald in there last night?! They made quite the snorechestra!"
When multiple people in a single room are sleeping and snoring, keeping other people in the room awake. These often happen in hotel rooms on family trips, busses, and hostels.
My parent's grand symphony snorechestra kept me up until two in the morning until I subtly threw a pillow at them from across the hotel room.