Given that most supergroups last little longer than a single album, it was easy to assume that Audioslave -- the pairing of Soundgarden vocalist Chris Cornell and the instrumental trio at the core of Rage Against the Machine -- was a one-off venture.

That suspicion was given weight by their eponymous 2002 debut, which sounded as if Cornell wrote melodies and lyrics to tracks RATM wrote after the departure of Zack de la Rocha, but any lingering doubts about Audioslave being a genuine rock band are vanished by their 2005 second album, Out of Exile.

Unlike the first record, Out of Exile sounds like the product of a genuine band, where all four members of the band contribute equally to achieve a distinctive, unified personality.

It's still possible to hear elements of both Rage and Soundgarden here, but the two parts fuse relatively seamlessly, and there's a confidence to the band that stands in direct contrast to the halting, clumsy attack on the debut.

A large part of the success of Out of Exile is due to the songs, which may be credited to the entire group but are clearly under the direction of Cornell, sounding much closer to his past work than anything in Rage's catalog.

Even the simple riff-driven rockers are tightly constructed songs with melodies and dramatic tension -- they lead somewhere instead of running in circles -- while the ballads have a moody grace and there's the occasional left-field surprise like the sunny, sweet psych-pop gem "Dandelion"; it's the strongest set of songs Cornell has written in a decade.

Which is not to say that Out of Exile is without excesses, but they're almost all from guitarist Tom Morello; his playing can still seem laborious, particularly when he clutters single-string riffs with too many notes (the otherwise fine opener, "Your Time Has Come," suffers from this), and his elastic stomp box excursions verge on self-parody on occasion.

Still, these are isolated moments on an album that's otherwise lean, hard, strong, and memorable, a record that finds Audioslave coming into its own as a real rock band.