Episode 3 - The Godfathers of Rock (ft. Led Zeppelin, Deep Purple & Black Sabbath)

The boys are back with a question that is as old as time itself (or at least since 1970): just who was it that invented hard rock and heavy metal? Steppenwolf may have been the first to use the term heavy metal (in Born to Be Wild), but the real roots of classic hard rock lie elsewhere.

The question is, where? 

Steve, Mark and Richard identify three locations as the possible source of the holy riff:

Birmingham - the beating industrial heart of England; London - the epicentre of cultural change as the floral Sixties slid into the flared, bell-bottomed Seventies; and Hertford - the leafy county town of the well-to-do. 

Representing them, respectively, are Black Sabbath with 1970's Paranoid, Led Zeppelin with their arguably peerless IV from 1971 and Deep Purple with their 1972 offering Machine Head)