After a prolonged set-up befitting the mini-orchestra she brought with her, St. Vincent’s Annie Clark took to Central Park’s Summerstage. She looked impossibly delicate as always, like someone might stop the show at any time to offer her a jacket. Of course, that impression dissipates quickly when she’s furiously punching feedback out of her guitar. The band’s set was only furious in bits though, mainly towards the end when they got to more active, nervous songs like “Marrow” or “Black Rainbow” from last year’s Actor. You often see a new band gone big-time and think, “Gee, this would really make more sense in a sweaty little basement.” St. Vincent is the exact opposite, with Clark’s elegant voice and her band’s sophisticated, jazz-lite arrangements a perfect score for an overcast metropolis. Seeing her on a dive bar stage now would be totally weird, like watching an exotic bird swoop in, touch down, order a drink. For the occasion, her touring band was supplemented by expanded horn and string sections, the versatility allowing them to ably handle a tricky song like “The Neighbors,” which she announced as a live debut. Like everything else played, it was upscale, exceedingly pretty, and actually sort of dull. The diverse crowd was ever appreciative, though never hopping or anything close. The sort of event where you’d look over to see the loudmouth kid who was just heckling the sound guy (to his credit, the bass was a little loud in the mix) passing a joint over the VIP barrier to an Upper West Side cougar. The music was just part of a pervasively pleasant park afternoon.