Symphony No.1 in Ab major Opus 55 (3) Edward Elgar Download 'Symphony No.1 in Ab major Opus 55 (3)' on iTunes
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Moments that rocked the classical music world
It's as simple as four notes piled on top of each other, known as the 'Tristan' chord because it's about a character called, well, Tristan. But this unassuming F, B, D sharp and G sharp played together was so unusual at the time that it's been causing debates ever since.