Plenty of pop artists try dressing up their songs in orchestral finery–it’s an isolated experiment, typically, and the subsequent return to a more modest scale is often greeted with relief. Rufus Wainwright’s recent Release the Stars (Geffen), on the other hand, is his third consecutive album to prominently feature elaborate instrumentation, and it’s becoming clear that it’s no gimmick but a key part of his aesthetic. Rock backbeats notwithstanding, it’s always been easy to find elements of musical theater and opera in Wainwright’s florid compositional style and overwrought, diva-worthy delivery, and now that he’s playing up those aspects, they work to underline his wickedly self-mocking sense of humor (lately he’s been partial to wearing monogrammed lederhosen). The arrangements here are so dense, really, that it took me three or four listens just to start unpacking them; only with familiarity do they reveal their beauty and precision. It’s hard to compare this stuff with Wainwright’s more stripped-down early work, but I’m certain now that this kind of grand ambition has been in him all along. The Magic Numbers and A Fine Frenzy open. a 7:30 PM, Pavilion, Ravinia Festival, Green Bay & Lake Cook Rds., Highland Park, 847-266-5100, $20-$45. A –Peter Margasak