Keyed trumpet

Early Classical era trumpet with keys

The keyed trumpet is a cylindrical-bore brass instrument in the trumpet family that makes use of tone holes operated by keys to alter pitch and provide a full chromatic scale, rather than extending the length of tubing with a slide or valves. It was developed from the natural trumpet in the 18th century and reached its high-point in popularity c. 1800 when two important trumpet concertos were written for it by Austrian composers Joseph Haydn and Johann Nepomuk Hummel, but waned with the invention of valves in the 1820s and the subsequent emergence of the modern valved trumpet. It is rarely seen in modern performances.

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