John T. Gast is a myth. Something of an enigma in the experimental scene, his music feels like entering into a fantasy world of wildly eccentric sound. His live set in the main Halle on Saturday morning began with a looping female vocal sample asking the crowd to "respect me." Bathed in red lights and using an iPad controller, mixing desk, torch and a small arsenal of pedals, he unleashed an onslaught of galloping dub rhythms and earworm melodies. The intensity reminded me of Dean Blunt's Babyfather performances. Halfway through, a large strobe light began flashing every three or four seconds for a solid 30 minutes. People thrashed around, creating a dizzying freeze-frame effect. One guy let out a string of hysterical loud screams in appreciation—or was it despair?