When you buy through links on our articles, Future and its syndication partners may earn a commission. Credit: Getty Images "Heavy metal and drop D is a match made in heaven," Soundgarden’s Kim Thayil ...

"Heavy metal and drop D is a match made in heaven," Soundgarden’s Kim Thayil once said, and for heavy rock riffs and thick-sounding chords, drop D is hard to beat. It's a simple one to set up, too: ...