
Flute
The flute is a musical instrument of the woodwind family.
The flute does not use reeds like a clarinet or saxophone, reeds but, is an
aerophone which produces its sound from the flow of air across an opening.
Flutes are generally categorized as Edge-blown aerophones.

The oldest flute believed to
have ever been discovered is a fragment of a cave bear femur. It was
discovered in Slovenia and dated to be about 43,000 years old. In 2008
another flute dated to be about 35,000 years old was discovered in
Germany. The five-holed flute has a V-shaped mouthpiece and is made from
a vulture wing bone.
A playable 9000-year-old bone flute made from the wing bones of
red-crowned cranes were excavated from a tomb in a Central Chinese
province of Henan.
A flute produces sound when a stream of air blown across a hole in
the instrument. This creates a vibration of air at the hole making
sound.
The air stream across this hole creates a siphon. This excites the
air contained in the usually cylindrical resonant cavity in the flute.
The player changes the pitch of the sound produced by opening and
closing holes in the body of the instrument. By varying the air
pressure, a flute player can also change the pitch of a note by causing
the air in the flute to resonate at a harmonic other than the
fundamental frequency without opening or closing any holes.
To make louder sounds, a flute must use a larger resonator, a larger air
stream, or increased air stream velocity. A flute's volume can generally
be increased by making its resonator and tone holes larger. This is why
a police whistle, a form of flute, is very wide for its pitch, and why a
pipe organ can be far louder than a concert flute: a large organ pipe
can contain several cubic feet of air, and its tone hole may be several
inches wide, while a concert flute's air stream measures a fraction of
an inch across.

The Western concert flute is
a descendant of the 19th-century German flute. It is a transverse flute
which is closed at the top. Near the top is the embouchure hole, across
and into which the player blows. It has larger circular finger-holes
than its baroque predecessors, designed to increase the instrument's
dynamic range. Various combinations can be opened or closed by means of
keys, to produce the different notes in its playing range. There are a
total of 25 working keys on a western concert flute. The note produced
depends on which finger-holes are opened or closed and on how the flute
is blown. There are two kinds of foot joints available for the concert
flute: the standard C foot (shown above) or the longer B foot with an
extra key extending the flute's range to B below middle C. There can
also be a Bb below middle c foot joint added to the instrument.
The standard concert flute is pitched in the key of C and has a
range of three octaves starting from middle C (or one half-step lower
with a B foot). This means that the concert flute is one of the highest
common orchestral instruments, with the exception of the piccolo, which
plays an octave higher. G alto and C bass flutes, pitched, respectively,
a perfect fourth and an octave below the concert flute, are used
occasionally. Parts are written for alto flute more frequently than for
bass. The contrabass, double contrabass, and hyperbass are other rare
forms of the flute pitched two, three, and four octaves below middle C
respectively.
Other sizes of flutes and piccolos are used from time to time. A
rarer instrument of the modern pitching system is the treble G flute.
Instruments made according to an older pitch standard, used principally
in wind-band music, include Db piccolo, Eb soprano flute (the primary
instrument, equivalent to today's concert C flute), F alto flute, and Bb
bass flute.