While Bill Withers is best known for funky, articulate tunes with roots in both soul and folk, his rich catalogue also includes collaborations with Bobby Womack (the fiery duet “It's All Over Now”) and jazz-fusion champs The Crusaders (the eight-minute odyssey “Soul Shadows”). And a 1972 live version of “Friend of Mine” from Carnegie Hall is a rousing sermon that confirms him as a commanding frontman.