horn, in music, any of several wind instruments sounded by vibration of the player’s tensed lips against a mouthpiece and primarily derived from animal horns blown at the truncated narrow end or, as among many tropical peoples, at a hole in the side. Metal construction, at first imitating natural shapes, dates as far back as the Danish Bronze Age lurs, cast in the shape of mammoth tusks, and the Roman buccina and semicircular cornu. Instruments of horn were known in ancient Egypt, Mesopotamia, Israel (the shofar), Greece, and throughout South and West Africa and continue to be played by shepherds in Scandinavia, the Balkans, parts of Spain, and Sudan.
Medieval European ivory horns, imported from Byzantium in the 10th century, were associated with royalty; these ivory (sometimes bone) horns, often richly carved, were called oliphants. The oxhorns of medieval huntsmen and watchmen sounded but one or two notes of the natural harmonic series—i.e., the notes produced on a horn or trumpet without finger holes or valves, caused by the air column vibrating in fractional segments (as for the fundamental note C: c–g–c′–e′–g′–b♭′ [approximate pitch]–c″–d″–e″, etc.). From these instruments later modern metal horns were developed. This process included refining the bore profile (which remains mainly conical except where impractical, as through the valve mechanism) and the bell form, and the prolongation of the bore to lower the fundamental pitch so as to bring higher notes of a tube’s natural series within the upper sound-wave frequency limit of a player’s lip vibration, thereby extending the instrument’s melodic possibilities. Horns retaining the curved shape but with lengthened tube include the 18th-century bugle horn. An English straight-built group, derived from early 19th-century hunting horns, includes the brass post horn (employing harmonics 2–5, written c′–g′–c″–e″ but sounding a sixth higher); the copper coach horn; and the 20th-century English hunting horn, a reduced version with one note only.
Accommodation of increased length by making one or more coils in the tube was well known in the 16th century, both in small once-coiled horns that led to continental hunting and post horns (whence the cornet) and in close-coiled helical horns with 5 or more feet (about 1 1/2 metres) of tubing. The large circular French hunting horn, the trompe (or cor) de chasse, appeared in about 1650; the modern orchestral, or French, horn derives from it. Still played in modern France and Belgium by huntsmen, brass bands, and horn-playing clubs, it varies in diameter and number of coils but is often about 15 inches (38 centimetres) across, coiled three times, with 15 feet (4 1/2 metres) of tubing. It is held on the player’s arm with one hand alone; the harmonics most used are numbers 4 to 12 (written in C but sounding in D a seventh lower), though numbers 2 and 3 are used as bass notes when the horns are played in harmony. See also French horn; mellophone; saxhorn.