Shoobie-doowie up-ba-ba. Aah-ahh-ahh-ooh-woo. Whoa-oh-oh-oh. It's easy enough to sing along at a Dr. Dog show—you just kinda make up the words as you go. Onstage, the band twinkle, lurch, swell, and roll, practiced in loose and sloppy delivery that sees band members switching instruments, singing harmonies, and swaggering behind unstyled hairdos and goofy sunglasses. The Philly five-piece are masters of the sunshine-pop hook, pouring as much slaphappy glee into a three-word chorus as into a five-minute breakdown. (Crocodile, 2200 Second Ave, 441-5611. 9 pm, $12 adv/$14 DOS, 21+.)