3 stars Third Man

At first glance, Jack White's latest side project, the Dead Weather, seems like a pointless enterprise. A blues-rock quartet in the obverse image of the White Stripes, the DW lets pasty-faced Jack sit behind the drum kit and pretend to be Meg, while pasty-faced Allison Mosshart of the Brit duo the Kills gets in front of the mike and pretends to be Jack. Kinda cool, but if Jack is playing drums that means Dean Fertitao is playing guitar, and though he's no slouch, he's also no Jack White.

Over the course of "Horehound," the method to White's madness reveals itself. Sure, "Hang You From the Heavens" is disappointingly desultory, and the closing "Will There Be Enough Water," sung by White, seems all too willing to slowly settle back into the primordial blues-rock swamp. But there's plenty of slamming, sludgy fireworks elsewhere, from a savage, obscure Dylan cover ("New Pony"), a PJ Harvey nod from Mosshart ("60 Foot Tall"), and a ripping, Oedipal duet ("Treat Me Like Your Mother").

Not nearly so thrillingly dynamic as the White Stripes, but a detour worth taking.

THE MARS VOLTA 'Octahedron'

3 1/2 stars Warner Bros

Vocalist Cedric Bixler-Zavala and guitarist Omar Rodriguez-Lopez wasted no time starting the Mars Volta after ending their speed garage band At the Drive In. Since rocketing to Mars, they've made smug prog-metal with psychedelic touches of free jazz that was sharp, cold, yet (if you disregard their oddball lyrics) surprisingly easy to understand, no matter how complex their rhythmic shifts may have been.

Yet, for all their dynamic range, they've never been warm or worried about melody until the quietude of "Octahedron."

With Red Hot Chili Peppers guitarist John Frusciante (a Volta constant) along for their most subdued and soulful effort, Mars Volta find buoyant, hummable composition at their command on the heartbroken likes of "Since We've Been Wrong" and "Teflon." These are, at their simplest, lovely melodies with weary lyrical embrace.

There's a curvaceous tenderness within "Octahedron" that's only been hinted at within Bixler-Zavala's laments or Rodriguez-Lopez's sonic leaps. Beyond passionate display, there's spaciousness - something no crammed-and-cramped Volta album ever had. "With Twilight as My Guide" is space rock in the most literal sense - dreamy, open, and crisp. Still, for all the roominess and ruined romance that Mars' men contemplate, there's hard steel (e.g., "Cotopaxi") found within "Octahedron's" dangerous curves.

JORDIN SPARKS 'Battlefield'

2 1/2 stars 19 Recordings

Challenged to name all eight "American Idol" winners, people tend to stumble over Jordin Sparks, the Arizona teen who won in 2007. Her second album will no doubt be successful, but it won't do much to establish her identity.

"Battlefield" is studded with brilliantly crafted, radio-ready selections, pluperfect pop tunes propelled by turbo-percussion.

The epitome of this approach is the title track, a rousing anthem by OneRepublic's Ryan Tedder. About the furthest Sparks gets from her comfort zone is the techno vibe of "S.O.S. (Let the Music Play)," which lifts its verse from the 1983 dance hit by Shannon.

Almost all the songs on this collection are smartly produced, with glossy surfaces and vivid arrangements. But in these settings, Sparks, despite an acrobatic and robust voice, (hear her roar on "Let It Rain") tends to get lost in the shuffle.

Still, the sine qua non for singers emerging from the "Idol" cookie cutter is picking good material, and Sparks is proving herself formidable on that battlefield.