“Jethro Tull would rehearse at a strict time every morning and then break for lunch. It was like going to work. In Black Sabbath, we never did that”: Tony Iommi on hanging out with Jimmy Page and Brian May, early Sabbath –and his time with Tull

Tony Iommi performs with Black Sabbath in 1976, when the band were getting more experimental, and tensions were rising.

Iommi’s innovations in Black Sabbath would not only prove to be influential on the sound of the genre in its most classic form, but would also spawn many of its offshoots and subgenres, from the doomy discordance of the self-titled track that opened their debut to the groove-metal thunder heard on the chromatic riffs of Sabbath Bloody Sabbath and the proto thrash of Symptom of the Universe.

Then there’s the more progressive side of his playing, exquisitely documented by lesser-known deep cuts like Megalomania, Spiral Architect and The Writ, where the bold stream of consciousness seemed to laugh in the face of musical boundaries and choose to follow no calling but its own.