Founded in 1987 by the American composers David Lang, Michael Jordan, and Julia Wolfe, the new-music collective Bang on a Can has weathered over three decades with its ecumenical, anarchic spirit intact. Since the pandemic began, this merry band has already organized two live online marathons. Now for the third, beginning at three P.M. E.T. Of 11 newly commissioned world premieres, three will be performed by the composers themselves. But novelty is by no means all. Bookending the program are Wu Man, champion of China’s ancient four-stringed pipa, and the pianist Jeremy Denk, taking a run on György Ligeti’s “Devil’s Staircase” étude, which has been described as both the loudest and the quietest piece ever written for piano—and also as totally bonkers. Lang, Jordan, and Wolfe co-host. —M.G.