NEW YORK — THE TANK-LIKE Mercedes SUV rumbled into Times Square one evening in late spring with all the subtlety of a space shuttle launch. It wasn't simply the boom-bip issuing at ear-splitting volume from the truck's bazooka speakers -- although the sound of kick drums that loud was enough to get passersby wondering, even complaining, about the person behind the wheel. You could see something else happening: hip-hop fans of all stripes having a "Hey, isn't that . . . ?" moment, connecting the music coming from the vehicle with its driver, New York "conscious" rapper Q-Tip.
The on-again-off-again front man-producer for seminal hip-hop quartet A Tribe Called Quest and one of the genre's most transcendent MCs, Q-Tip largely has kept to himself since 1999, when his last album, "Amplified," hit No. 4 on the national hip-hop/R&B chart. Outside of a scant few guest verses on other performers' songs (including the Chemical Brothers' European smash hit "Galvanize," for which Q-Tip won a Grammy) and dribs of production work for the likes of Stevie Wonder, Mariah Carey and Mobb Deep, he's remained virtually silent. Rap aficionados, meanwhile, never forgot him.

