From the article: "Chowning soon started teaching conventional music classes at Stanford, but spent evenings in the lab exploring what he called “spatial illusi

From the article: "Chowning soon started teaching conventional music classes at Stanford, but spent evenings in the lab exploring what he called “spatial illusions”: the impression, for instance, that a whisper is nearby or an explosion distant. Spatialisation appeals to our primal impulses, he says. “Is the predator close or far? It sends a signal right to the amygdala: freeze, fight or flee. It’s very compelling.” He also developed a method of programming hyperspeed vibrato-like motion between two electronic notes. At a high frequency, the wobbly pitch merged into one thick tone. To his surprise, tweaking the inputs changed its timbre: one moment a gong-like drone, the next a reedy whistle. Chowning had discovered digital frequency modulation, later called FM synthesis. He modestly describes it as a “a gift from nature” "