It's likely that a decade after its debut record this band now has fans who might ask, "You mean Dave Grohl was in a band before the Foo Fighters?" But they, or any Foo followers who pine for the increasingly refined vocals and polished pop-punk uniformity of the first four albums, will swallow this one whole--or at least half. For as much as vocalist/bandleader Grohl and Co. mix a similar concoction on the 20-song double CD, they manage to agitate the formula ever so slightly. Disc one follows the Foo's classic sonic blueprint: lip-smacking melodies and enigmatic lyrics, double-barrel guitars and drums that attack. But songs take a gentle turn on the second CD, showcasing Grohl's underrated vocals amidst a high-energy ensemble of acoustic guitars, piano and mandolin (by studio guest John Paul Jones of Led Zeppelin). Singing, not shouting, Grohl flips potential teen-rock anthems like "Miracle" and "Cold Day in the Sun" (with drummer Taylor Hawkins handling lead vocals) into impending adult-oriented radio staples and, 11 years after Nirvana, the Foo Fighters may finally have their triumph.