Wind instrument of ancient origin formerly made of wood but now of silver and other metals. From medieval times two methods of producing sound were used: (a) blowing across a round mouth-hole as on the panpipes or transverse (side-blown) flute; (b) blowing into a whistle mouthpiece (end-blown) as on the recorder or flageolet.
The word flute was used indiscriminately to denote both types during medieval times, but in the baroque period flute or flauto specifically meant the end-blown recorder. The modern flute is descended from the German (transverse) flute. Whereas today it is cylindrical in bore, stopped at one end, until the early 19th century it was conical. The player's breath sets in vibration the column of air inside the tube. Acoustically, the tube acts as an open one; the mouth-hole serves to prevent its acting as stopped and thus sounding an octave lower. The body orginally had one thumb-hole and from four to eight finger-holes. The first key was added in 1677, the second in 1726 by Quantz, flute teacher of Frederick the Great. The great flute virtuoso of the Bavarian Court Orchestra, Theobald Boehm, used an eight key flute, but revolutionized the instrument in 1832 with his 'ring key' system. In 1847, he produced a fifteen hole metal instrument with 23 keys and levers.
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