aerophone

Any musical instrument in which air is the main vibrating agent. Aerophones form one of the main categories of instruments in the standard classification of Hornbostel and Sachs (1914). They are subdivided into types according to (a) the main material they are made of, and (b) how the air is set in motion (via a mouthpiece, a reed, or neither).

An aerophone is any musical instrument which produces sound primarily by causing a body of air to vibrate, without the use of strings or membranes, and without the vibration of the instrument itself adding considerably to the sound.

The first class (41) includes instruments where the vibrating air is not contained by the instrument itself, such as the bullroarer. This class includes free reed instruments, such as the harmonica, but also many instruments unlikely to be called wind instruments at all by most people, such as sirens and whips. This class includes almost all the instruments generally called wind instruments in the west, such as the flute, the oboe and the trumpet. Instruments such as the calliope (and steam whistle), as well as the pyrophone might thus be considered as class 42 instruments, despite the fact that the "wind" or "air" may be steam or an air-fuel mixture.