For 15 years, Black Rebel Motorcycle Club has carried the torch for true rock and roll. The latest edition of the firebrand rock troupe, sees them at their most dynamic. Their sixth studio album, "Specter at the Feast," ventures into diverse sonic territory, delivering their most ambitious offering yet. It's an album of impossible dichotomies; opposing sounds amalgamate into a seamless, entirely coherent package, that rumbles with driving rhythms, and soars with skyward-arcing guitar howls. Robert Been delivers growling bass grooves on "Hate the Taste," and Peter Hayes' guitar wails on what may be their most hard-rocking song, "Rival."