Jennifer Lopez has a singing voice like a helium balloon made out of cotton candy. Then again, having a strong, distinctive, or even adequate voice has never been a prerequisite for the kind of heavily processed, aggressively produced bubble-gum R&B and pop that J to tha L-O specializes in. Besides, singing represents only a fraction of the skill-set necessary for Lopez's synergistic brand of pop divadom: Modeling, acting out the bland sentiments of hacky songsmiths, and especially dancing appear to be equally important gifts. Besides, Lopez's songs serve as little more than glossy blueprints for videos showcasing the sex appeal, fashion savvy, and mad dancing prowess that made Lopez the flyest of all Fly Girls back in the day.

Lopez's exceptionally thin voice hasn't stopped her from cranking out a steady stream of pop hits, which continues with "Get Right," the maddeningly catchy first single from her new Rebirth. More than any of her other smashes, the song illustrates just how irrelevant Lopez's crooning is to her chart success: Producers Rich Harrison and Cory Rooney could easily slip Lopez's whisper of a vocal out of the mix, leaving just funky drumming and furious, staccato horn bursts. Lopez scored co-writing credits on only two of the album's 12 tracks, including the inevitable remix of "Get Right" with Fabolous. That's surprising, given the avalanche of clichés and unconvincing hip-hop 'tude that constitute the album's lyrical content (faithfully recreated in the album booklet, along with numerous glamour shots of Lopez). Still, though Lopez often comes off as little more than a featherweight studio concoction, Rebirth contains a few moments with the sugary snap of fresh Bubble Yum. "Cherry Pie," for example, while sadly not a Warrant cover, sounds like the kind of salacious, infectious trifle that Prince might have written for Vanity 6 or Sheila E. in the '80s. Rebirth's first half packs a certain fizzy effervescence, but the album sags as it approaches the finishing line, and it does little to refute the notion that Lopez's most magical musical moments can be found, free of charge, playing incessantly on Top 40 radio.