In the course of Roulette’s evolution, from its humble beginnings in a Tribeca loft, in 1978, to its present home in Brooklyn, the venue has become one of New York City’s most steadfast bastions of experimental music; there’s so much going on this week that you scarcely need to look elsewhere for aural intrigue or edification. On Dec. 5, the excellent Momenta Quartet collaborates with the composers Elizabeth Brown and Frances White in pieces that draw on Japanese folk music, Persian poetry, and a W. G. Sebald novel. The following night celebrates Sylvano Bussotti, a trailblazing Italian avant-garde composer and queer activist; Gamelan Kusuma Laras, a group that specializes in courtly Javanese repertoire, performs on Saturday. On Dec. 9, the Anagram Ensemble introduces “I Looked at the Eclipse,” a new opera by James Ilgenfritz and Sarah Krasnow which incorporates improvisation and video, and, on Dec. 10, Judith Berkson, a distinctive composer, vocalist, and cantor, presents new music with the protean ensemble Ordinary Affects.