"The common consensus is that Black Sabbath were the first heavy metal band. And maybe they were. But that doesn’t mean they wrote the first heavy song. Because while Ozzy and co. certainly took the concept of intense, sinister music played by evil-looking dudes to new sonic and visual heights, there were plenty of unnerving sounds designed to scare the bejesus out of listeners being created well before Tony Iommi’s deathly Black Sabbath tritone riff signaled the end (or the beginning?) of the musical world as we know it."