This two-CD set of early-1970s Bob Marley tracks recorded by the legendary Jamaican producer Lee Perry illustrates the huge difference the revolutionary reggae producer made to the band's sound. The polite ska rhythm of the '60s is gone, replaced by upfront rhythm guitar and bass and Carlton Barrett's exemplary one-drop reggae drumming, while Marley's vocals are tougher and more confident. Peter Tosh's vocal on "Go Tell It on the Mountain" has the authority of a Biblical prophet, and Perry impeccably captures the sheer weirdness of the spooky "Duppy Conqueror."