"We've played a Mozart piano concerto where the soloist literally skipped the entire development, " Mr. Bauch says.

WSJ: Orpheus Chamber Orchestra | Personal Code of Conduct | By Corinna da Fonseca-Wollheim

Haydn's horn concerto, Mozart's four horn concertos, and Beethoven's sonata for horn and piano were all written for natural horn, although they're usually played today on valve horn.

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