Once ordained the world's loudest rock band by the Guinness Book of World Records, Deep Purple started off humbly enough. Their '68 debut Shades of Deep Purple featured mostly covers and contained little to set the band above a raft of Acid Rock novelty acts that included Iron Butterfly, Quicksilver Messenger Service and the Electric Prunes. Atrociously produced, even by '60s standards, the album's one saving grace is "Hush," a song that pits Ritchie Blackmore's wrecking-ball guitar against Jon Lord's sermonizing organs, auguring great things to come. Deep Purple in Rock (1970) and Fireball (1971) document the band's evolution from generic Psychedelic rockers to Heavy Metal pioneers. The band's power peaked the following year with Machine Head, a record that split the difference between Blue Cheer and Black Sabbath. "Smoke on the Water" quickly became their theme song, but deeper cuts like "Highway Star" and "Space Truckin'" are equally impressive. These songs make you want to double the speed limit and run from the law just for the hell of it, which is what any good rock song should do. The remaining years of the decade marked a turbulent, and frankly uninteresting period for the band, but things picked up again for Deep Purple when the classic Ian Gillan/ Ritchie Blackmore/Jon Lord/Roger Glover lineup reconvened to release the radio-complaisant Perfect Strangers in 1984. Foregoing the headbanging intensity of their '70s material for a polished, more Progressive Rock sound, the record (at least) had the distinction of directing a new generation of listeners back to the band's early classics.