a valved brass musical instrument built in coiled form and pitched in E or F, with a compass from the second A or B below middle C to the second E or F above. The alto and tenor forms substitute for the French horn in marching bands. In the 1950s a version called the mellophonium was developed for concert use; its French horn-style bell faces forward. The mellophone bears no relationship to the melophone, a free-reed instrument
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