Someone really ought to do something about those disorderly kids in Sonic Youth; tell the band to act its age already. Many of the group’s well-mannered contemporaries have realized they can satisfy a crowd by playing a set of old favorites, but not Sonic Youth. It has to prove its currency by subjecting audience members to new material. Fortunately, this is the best reason to see a Sonic Youth show in the first place.

Philadelphia’s Electric Factory hosted a recent stop on the Sonic Nurse tour. The opening slots were filled with avant-garde troupes prepared to earn mixed reactions from the crowd. The raunchy, primitive buzz and rant of Magik Marker tried to erase the barrier between band and audience; it nearly succeeded. The group even lent one of its guitars to a curious member of the crowd so he could join in on the noise-jam finale. Fursaxa followed, unleashing its rapturous haze with guest musicians from local psych-rock favorites Bardo Pond (Isobel Sollenberger and brothers Michael and John Gibbons joined Fursaxa onstage). The clash of pleasant/abrasive drones ranged from tribal thumps to airy waves of guitar and flute.

Sonic Youth took the stage and seemed determined not to trip through its past. The band dodged requests for old favorites as it blasted through nearly half of the recently released Sonic Nurse. And that was just the opening. Sonic Youth stood behind its music with a confident voice (Kim Gordon) and eccentric enthusiasm (Thurston Moore). The frenzy of the Gordon-sung “Pattern Recognition” led into a Moore guitar-noise solo that escalated to some handy guitar picking courtesy of his two front teeth, all while rolling around on a speaker cluster. His body twirled beneath yellow flashes of light from above, and for a moment, he was the young rock star at the center of the world. Not bad for a 46-year-old avant-rocker.

The crowd would not be denied a handful of classics from 1988’s Daydream Nation and 1992’s Dirty, two of the band’s favorite albums to play live. Moore fed a distorted version of Tiffany’s mall-pop classic “I Think We’re Alone Now” through a fuzzy amp before jumping into Sonic Youth’s seven-minute opus about adolescent confusion, “Teenage Riot.” The song sequence revealed a band that still enjoys throwing a pie in the face of pop culture once in a while. Sadly, sound problems muddled the performance.

Sonic Youth tore through guitarist Lee Ranaldo’s major Sonic Nurse contribution, “Paper Cup Exit,” and the rhythm section of Steve Shelley and Jim O’Rourke led an extra-choppy, grooved-out rendition of “100%.” Gordon polished off the set with a gritty, yelping version of “Drunken Butterfly.” The encores proved the group’s recent material (“Rain On Tin” from 2002’s Murray Street) fared well alongside earlier work (“Shadow Of A Doubt” from 1986’s EVOL). Those waiting for the Sonic Youth nostalgia tour may have to wait for the band to mature. Good luck.