In trying to find out what kind of instrument the voice is, we need to take a look at how instruments are divided into families. The traditional orchestra is divided into four families - Brass, Woodwinds, Strings and Percussion. But acoustic scientists (scientists who work with sound) divide instruments into five types, depending on how the instrument vibrates:


Chordophones - in which strings vibrate - like violins, cellos, etc.

Aerophones - instruments that work with air - like flutes, clarinets, pipe organs and trumpets

Membranophones - instruments that work with thin stretched skins, like drums

Idiophones - things where what vibrates is a solid thing, like xylophones, rhythm sticks, bells and gongs

Electrophones, where electricity creates the sound - like synthesizers, radios, tvs
Of course, there are combinations of the above types. The kazoo, for example is a combination of membranophone (the buzzing paper is a membrane) and an aerophone (you have to blow in it to make it work).

To understand what kind of instrument the voice is we have to take a look at how your body is put together - something called anatomy.

The voice starts with an air pump - the lungs.

The air comes up through your trachea up to the thing in your throat called the larynx. Put your hand on your throat and find the big bony thing at the front often called the adam's apple - that is the larynx. Inside the larynx are two flexible vibrating things called vocal cords. Actually "cords" is not really a good name, because they are not string at all, but rather flexible stretchy material more like a stretched piece of balloon.

These two stretchy things are what vibrate. How much your vocal cords are stretched makes your voice higher and lower - the looser your vocal cords, the lower the sound, and the tighter, the higher.

Then as the sound goes up into your mouth, the shape of your mouth (and the shape of your sinus cavities in your face and nose) change the sound even more, to create a wonderful flexible instrument capable of sounding like Louis Armstrong or Britney Spears or Bobby McFerrin.

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Your voice is most like "C" - a kazoo! Sure, the voice is an aerophone - an instrument in which air vibrates, but it is also a membranophone, because of the vibrating vocal cords.
You are a kazoo!
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