Crook (music)

"*Cor solo*" (natural horn) – Raoux, Paris, 1797 – Paris, Musée de la Musique (with a double-loop crook located within the body of the horn).

A crook, also sometimes called a shank, is an exchangeable segment of tubing in a natural horn (or other brass instrument, such as a natural trumpet) which is used to change the length of the pipe, altering the fundamental pitch and harmonic series which the instrument can sound, and thus the key in which it plays.^[1]

^ Apel, pp. 392, 926.

[Apel-1] Apel, pp. 392, 926.

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