At this point, Sonic Youth can't make an album that doesn't sound like Sonic Youth, but the band has found a vital muse by jiggering with its tail-chasing condition over the past few years. Starting with 2000's grimy and spectral NYC Ghosts & Flowers, the group has been at work on a trilogy devoted to New York City. Murky even in Ghosts' most literal moments, the premise at first seemed like little more than coy redundancy for a band so famously linked to its hometown. But that wry acknowledgment of insularity proves central to the new Murray Street, the trilogy's second installment. This may be a lot to read into a muted little sample, but the key to Murray Street seems rooted in a sardonic round of applause that finishes off the seven-minute noise outro to "Karen Revisited." The blasé clapping adds funny punctuation to Lee Ranaldo's song of fever-dream remembrance. More importantly, though, it smacks of Jim O'Rourke, the newly enlisted production guru likely responsible for Murray Street's forays into jam-band noodling and polished '70s riff-rock. Buoyed by crystalline guitar tones and leisurely stabs at lighter-raising tunefulness, a good deal of the album showcases a band joyfully copping to the Grateful Dead and Thin Lizzy records in its collection. The rest of Murray Street confirms that the band is still giddy about being Sonic Youth. Filling the roles they were meant to play, Thurston Moore applies his endearingly stunted poetics to rousing ends, while Kim Gordon sings ghostly hymns about plastic girls with plastic guns. Murray Street doesn't mark an epochal moment for Sonic Youth, but its familiar nods and new ingredientsfrom Steve Shelley's occasionally near-funky drumming to O'Rourke's tingly laptop texturesstake out another high point for a band achieving self-realization by reconciling self-absorption with a sigh and a smile.