Girls run the world. But who runs the girls? For most of the past 10 years, the answer has been Beyoncé Knowles. In the Estrogen Era - a period in which women seized pop music's center stage - Beyoncé has been the prima donna, the diva of divas: the girl with the funkiest songs, the flashiest Bob Fosse-meets-hip-hop dance moves and, as Kanye West memorably declared, the Greatest Video of All Time.

Beyoncé is such a force of nature that it's easy to overlook her trump card: She's a bit of a weirdo. Not a weirdo like her stiffest competition, Lady Gaga. (Wearing sirloin to an awards show isn't B's style.) Her weirdness is musical - it's in the idiosyncratic way she syncopates her vocals, the odd melodies she floats over rugged beats, her sui generis mix of rap bravado, gospel sanctimony and old-fashioned showbiz razzle-dazzle. It's in songs like "1+1," the ballad that opens her fourth album. The track begins like the lowest-fi indie rock: a few raggedy guitar arpeggios, a discreetly piping organ. It stays there, more or less, while Beyoncé sings a meandering melody, crooning, groaning and whooping about the comfort of love - and sex. "When my days look low/Pull me in close and don't let me go/Make love to me," she sings.  

4 might be her strangest rec­ord. It's a big-budget megapop album with an A list of guest stars (Kanye West, André 3000) and songwriter-producers (Tricky Stewart, the-Dream, Diplo, Ryan Tedder, Diane Warren). Yet it's as eccentric - as unmistakably personal and quirky - as anything that Sufjan Stevens ever cooked up in his bedroom.

Beyoncé has made a career of setting trends, and on 4, she leaves fashionable production styles behind. There's no Eurodisco thump; live instruments take the place of digital beats on many tracks. Half the songs are ballads, but all kinds of sounds filter through the mix - vintage soul, hard rock, reggae, adult contemporary. Beyoncé calls Nigerian Afrobeat legend Fela Kuti a big inspiration (Jay-Z is co-producing the Fela! musical), which may explain the bristling brass arrangements in "Countdown," a dancehall-style corker, and in "End of Time," whose martial beat drives home a command: "Say you'll never let me go!"

That song, like many on 4, is a steamily sensual ode to monogamous romance. Beyoncé has been a star for more than a decade, but now she's a 29-year-old married woman, and she sounds like one, singing love songs that are no less sexy for being unblinkingly true to life. "There's ups and downs in this love/Got a lot to learn in this love/Through the good and the bad, still got love," she growls in "Countdown."

The low point comes in "I Was Here," a blowsy Diane Warren ballad swamped in "My Way"-style self-mythologizing: "I was here/I lived, I loved/I was here/I did, I've done/Everything that I wanted." Beyoncé sings with authority, but sounds off; she's a diva, Lord knows, but she's never been a preener, a navel-gazer. She's too busy with other stuff: singing, dancing, following her muse, loving her man, running the world.

Listen to "The Best I Never Had":

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“More Than a Feeling”

Boston mastermind Tom Scholz was as surprised by anyone when he sent his unsolicited demo to record labels and got back a positive response. Scholz said, “I couldn’t believe it. Nobody knew who we were, so I wouldn’t even say we were struggling. It was groveling.” Part of the credit for the interest must go to the anthemic rock number "More Than a Feeling." Inspired by the Left Banke's 1966 hit "Walk Away Renee," Scholz worked on the song for five years in his basement studio before it was released on this album.