Class of wind instruments that usually have a conical opening or derive from an animal horn or tusk. Horns are sounded by the vibration of the player's lips against a mouthpiece (as with a trumpet).
Animal horns that produce one or two notes when the player blows through a hole are found in many cultures. Such horns include medieval hunting horns, royal African ivory horns, the Roman cornu, and the Jewish shofar.
Such instruments were imitated in metal and gave rise to horns such as the great lur of ancient Scandinavia. Other instruments of animal-horn ancestry include the alphorn, bugle, cornet, and Renaissance cornett, a wooden horn with finger holes. The orchestral horn, or French horn, was developed about 1650 in France and is a large version of the smaller crescent-shaped horns that had been redesigned with circularly coiled tubing. The French hunting horn, which entered the orchestra in the early 1700s, produced about twelve tones of the natural harmonic series. The horn gained greater flexibility about 1750 with the invention of the technique of hand-stopping. Hand-stopping involves placing a hand in the bell of the horn to alter the pitch of the natural notes by as much as a whole tone. Despite this advance, cumbersome lengths of tubing, called crooks, were necessary for playing in many keys.
The invention of valves in the early 19th century revolutionized the horn, allowing the player to alter the length of the tubing by the motion of a finger. A horn in the key of F with three valves can produce a chromatic scale over three octaves, running upward from the B below the bass clef (notated a fifth higher). Modern players use hand-stopping to affect intonation and tone color. The modern horn in F has three valves, circular coils of narrow tubing flaring at one end to a wide bell, and a funnel-shaped mouth piece that accounts for the horn's soft, mellow tone. The double horn in F and B-flat, introduced about 1900, is rapidly superseding the F horn. Equipped with an extra valve to switch to the B-flat tubing, it offers certain technical advantages. Most modern orchestras include four horns. The so-called English horn is actually a deep-toned oboe.
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