Andrew W.K. introduced his quiet new self in his typically overstated fashion Sunday at Pianos. He didn't wear the sweat-stained whites that are his uniform; he dressed all in black. And he didn't karate-kick out the jams that made him semi-famous (“Party Hard,” “Party Till You Puke,” “It's Time to Party,” etc.); he hunched over a piano hugging stage left. W.K. sprinted through a half-hour of newly penned songs and covers punctuated by the occasional bout of free-form ivory pummeling. There was no head-banging, no mosh pit, and no blood. But once the crowd started thinning in the back, devotees were treated to the payoff they must have seen coming: After a fifteen-second encore, W.K. sat down and tore through “I Get Wet,” leading the crowd through the raucous shout-along chorus they all paid $10 for. —David Bevan