Brass instruments

A brass instrument is a musical instrument that produces sound by sympathetic vibration of air in a tubular resonator in sympathy with the vibration of the player's lips. Brass instruments are also called labrosones, literally meaning "lip-vibrated instruments".

There are several factors involved in producing different pitches on a brass instrument. Slides, valves, crooks (though they are rarely used today), or keys are used to change vibratory length of tubing, thus changing the available harmonic series, while the player's embouchure, lip tension and air flow serve to select the specific harmonic produced from the available series.

The view of most scholars (see organology) is that the term "brass instrument" should be defined by the way the sound is made, as above, and not by whether the instrument is actually made of brass. Thus one finds brass instruments made of wood, like the alphorn, the cornett, the serpent and the didgeridoo, while some woodwind instruments are made of brass, like the saxophone.

Modern brass instruments generally come in one of two families:

There are two other families that have, in general, become functionally obsolete for practical purposes. Instruments of both types, however, are sometimes used for period-instrument performances of Baroque or Classical pieces. In more modern compositions, they are occasionally used for their intonation or tone color.

Brass instruments may also be characterised by two generalizations about geometry of the bore, that is, the tubing between the mouthpiece and the flaring of the tubing into the bell. Those two generalizations are with regard to

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