Metal bands and horror films stoke sonic dread the same way 18th century composers did—with a forbidden sequence of notes known as the “devil’s interval.”
Think of the first two notes of Jimi Hendrix’s “Purple Haze” or Metallica’s “Enter Sandman”—or American police sirens.
Click through for all the meaty details on the Devil’s Interval. Oh, and Happy Halloween!
Source: Devil’s interval: What makes music sound scary? — Quartzy
The Practice of Practice 