Brass Instrument
A brass instrument is a musical instrument that uses a cupped mouthpiece shaped in a way that allows the player's lips to vibrate to generate the instrument's sound. Brass instruments are usually, but not invariably, made of brass. Similarly, in musical terms, not all instruments constructed from brass belong in the category of "brass instruments"; a notable example is the saxophone, which, although usually made of brass, is a woodwind instrument.
Because the player has direct control of the prime vibrator (the lips), brass instruments exploit the player's ability to select the harmonic at which the instrument's column of air will vibrate. By making the instrument about twice as long as the equivalent woodwind instrument and starting with the second harmonic, players can get a good range of notes simply by varying the tension of their lips (see embouchure). Brass players call each harmonic a "partial".
Brass instruments generally come in one of three families:
- Natural
brass instruments, where the player can only
play notes in the instrument's harmonic
series, for example the bugle.
The trumpet
was a natural brass instrument prior to about
1795, and the French
horn before about 1820.
- Valved
brass instruments use a set of valves (typically
3 or 4 but as many as 7 or more in some cases)
operated by the player's fingers that introduce
a additional lengths of tubing into the instrument,
changing its overall length. This family includes
the modern trumpet,
cornet,
flugelhorn,
saxhorn,
euphonium,
tuba,
Sousaphone,
mellophone,
and French
horn. The valves are usually piston valves,
but can be rotary values. Rotary valves are
the norm for the French
horn and are also prevalent on the tuba.
- Slide
brass instruments use a slide to change the
length of tubing. The main instrument in this
famility is the trombone
(although some valve trombones are also made)
and the slide trombone's ancestor the sackbut.
Some modern trombones also have rotary valves
in addition to the slide. The folk instrument
the bazooka
is also in the slide family.
The trumpet, trombone, French horn, and tuba are the brass instruments most often found in a symphony orchestra. See also wind instrument.
For a comparative list of the pitch of various brass instruments see pitch of brass instruments.