what was the first feature-length film to use vitaphone technology
Vitaphone The business was established at Western Electric's Bell Laboratories in New York City and acquired by Warner Bros. in April 1925.[2] Warner Bros. introduced Vitaphone on August 6, 1926 with the release of their silent feature Don Juan, which had been retrofitted with a symphonic musical score and sound effects. There was no spoken dialog. The feature was preceded by a program of short subjects with live-recorded sound, nearly all featuring classical instrumentalists and opera stars. The only "pop music" artist was guitarist Roy Smeck and the only actual "talkie" was the short film that opened the program: four minutes of introductory remarks by motion picture industry spokesman Will Hays.