As the Hudson is tidal all the way to Troy, it’s perhaps unsurprising that a chunk of hippest downtown Manhattan should have drifted so far upstream, supplanting the rusty old town of Hudson, New York. Geography is immaterial, though, as this annual festival migrates to cyberspace, bearing such gifts as a worldwide interactive Zooming of the late Pauline Oliveros’s Tuning Meditation, and the species-breaching clarinetist and philosopher David Rothenberg—from his perch on the Hudson in Cold Spring—jamming with the Turkish computer musician Korhan Erel and a nightingale, both in a park in Berlin. —E.E.