When did sound in film first show up?
Sound film
At the University of Illinois, Polish-born research engineer Joseph Tykociński-Tykociner was working independently on a similar process. On June 9, 1922, he gave the first reported U.S. demonstration of a sound-on-film motion picture to members of the American Institute of Electrical Engineers.[22] As with Lauste and Tigerstedt, Tykociner's system would never be taken advantage of commercially; however, De Forest's soon would.