A cassette tape unraveling through water and a phonograph stylus gliding on shimmering vinyl are just two of the images filmmaker Matt Wolf uses to illustrate the aqueous, abstract sounds of avant-garde musician Arthur Russell. A cellist, composer, poet, and singer, Russell was only 40 when he died of AIDS in 1992, but he left behind a large body of work that, thanks to reissues and new pressings, is finally reaching the larger public he craved. Though his early collaborations with David Byrne and Robert Wilson weren’t successful, Russell had a run of disco hits released under various pseudonyms in the early 80s, and his later forays into ethereal “echo” music were even more productive. 71 min.