2. Black Sabbath (1970): Reportedly, principle recording for the entire album took place over the course of 12 hours. The band had all of their equipment mic’d, and they merely played through their set in the studio, with most of the tracks on the album having been captured in one take. Iommi’s solos are largely overdubbed though, and this album contains some of his best. The heaviest track on the album is the namesake of the band, which burrowed thematic influence heavily from Mario Bava’s film Black Sabbath and the song is also significant for its use of the “devil’s tritone” interval —a sound so sinister that it was outlawed during the renaissance.