David Randall Thom (born August 21, 1951) is an American sound designer and the director of sound design at Skywalker Sound.
Thom started his film career by phone calls to Walter Murch, who invited him to visit a re-mix of American Graffiti. Thom introduced himself to Murch, Ben Burtt, and Mark Berger, and he said he had been working for a radio station in Berkeley and wanted to work in film sound.
Description above from the Wikipedia article Randy Thom, licensed under CC-BY-SA, full list of contributors on Wikipedia.