A German Requiem Opus 45 (5) Johannes Brahms
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Cutting-edge sounds: what is classical music's iPhone 5?
It might not sound like it's on the same scale as touchscreen technology, but when Haydn's trumpet concerto showcased a keyed trumpet, it was like Apple announcing they're planning a space mission. Simply, no-one had ever heard a trumpet played like that before. All previous trumpet works were limited by the ability of the player to use their lips and mouth to change the limited number of notes.