A constantly surprising and ridiculously fun acid test of modern, experimental, and inside-out sounds, the Bang on a Can Marathon also unofficially kicks off New York’s annual summer orgy of free music (see: “Make Music New York” on Tuesday). At this year’s marathon, some 150 musicians will perform dozens of works over 13 hours. Where else can you travel the spaceways with the Sun Ra Arkestra; hear the Prism Quartet play Iannis Xenakis; catch up with recent works by intrepid BOAC founders Michael Gordon, Julia Wolfe, and David Lang; see the Bang on a Can All-Stars perform two pieces by—and with—Philip Glass; and come together when the Glenn Branca Ensemble brings everything to a screaming, climactic, midnight finale with Branca’s hour-long The Ascension: The Sequel—all in the course of a single ear-bending day?

Sun., June 19, 11 a.m., 2011