Multiphonics is the process of blowing vigorously into a saxophone to produce a collection of notes.
More about saxophone:
A saxophone comprises a clarinet-like mouthpiece and a conical metal tube with around 24 apertures that are controlled by cushioned keys. The tube was originally made of brass.
There are a handful of fingerings one can utilize to play what we call "multiphonics," or more than one note at once, on the saxophone, whereas it isn't possible to play a whole set of chords on the instrument. These work best as an odd-sounding impact rather than to play chord tones or traditional harmonies.
