To help celebrate the anniversary of Experimental Intermedia, this Wednesday at 9:00pm John Hudak, Bruce Trotsky, and two Apple Powerbooks will perform "Modification 3: a Digital Feedback System." The musicians and machines promise that their collaboration will result in audio controlling video and video controlling audio, equally. FYI: Experimental Intermedia has been supporting musicians and artist experimenting with "intermedia" since 1968. The concert takes place at 224 Centre Street in Manhattan.