The Roots, ''Rising Down'' (Def Jam): Over the course of 15 years and seven studio albums - ''Rising Down'' being their eighth - The Roots have shown they're not here to party.

Not to suggest that the Grammy-winning, critically revered hip-hop band is dreary, but even when they tackle a subject that seems to be frivolous, like girls, as on the iTunes exclusive ''Birthday Girl'' with Fall Out Boy's Patrick Stump, it takes a serious tone: On that track, Black Thought offers a conflicted view on jailbait. On their most political - albeit uneven - CD to date, the Roots pull no punches, intelligently addressing pharmaceutical companies and global warming (''between the green house gasses, Mother Nature's spinning off its axis'') on ''Rising Down,'' and, on the undulating Fela Kuti-inspired ''I Will Not Apologize,'' the quest for integrity.

The music matches the lyrical intention, thick with foreboding (even claustrophobic) droning synths, much like those anchoring ''Get Busy.'' As usual, the Roots are motivated by drummer/ producer ?uestlove's boom-bap - this is the lone rap act where the rapper isn't the star, which can be problematic. Although he's got much to say, Black Thought tends to say it with little inflection. Even his ''solo'' ''75 Bars,'' which refers to him spitting for 75 bars straight, begins to drag, as if changing things up equals watering things down. It's not good when the guest stars - fellow MCs Mos Def, Saigon and Dice Raw - almost steal the show.

Ultimately, ''Rising Down'' will confirm what you like - or for some, dislike - about The Roots.

By AMY LINDEN For The Associated Press

-Check out The Roots' Discography

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