When you go on those odd snorkeling tours in tropic places and theres a lot of people snorkeling in one area. You can hear all the strange breathing all around you, making a harmonic sound with the water in your ears. It gets pretty loud, and is usually characterized by the awkwardness of hearing a snorkeling noise getting louder, then bumping into a hot chick or ugly old lady clad in a bikini that you don't know.
I'd normally go on those cool snorkeling tours but those I'm tired of those annoying Snorkestra symphonies.
The act of multiple people snoring while asleep. mainly in a loud and annoying fashion.
"Geeze, did u here bob and joe last night, it was a snorkestra in there!"
"That orchestra was so horrible that they could have been confused with a snorkestra"