I came across a BoingBoing post about the so-called Devil’s Interval, a musical form suppressed by the Church in the Middle Ages.
The post also talks about a new heavy metal documentary which ties the Devil’s Interval, a specific kind of musical interval that spans three whole tones, with the history of heavy metal.
See the BBC’s report called The Devil’s Music (with mp3 examples), and if it floats your boat, the metal history site (with documentary trailer) Metal: A Headbanger’s Journey.
Oh, and for the record, I’m pretty sure Xeni was just joking when she said, “When you play Wagner backwards, it goes, ‘I LOVE SATAN’. But nevertheless if that’s what you want to hear…