Mickey Mouse
Audiences at the time of "Steamboat Willie"'s release were reportedly impressed by the use of sound for comedic purposes. Sound films or "talkies" were still considered innovative. The first feature-length movie with dialogue sequences, "The Jazz Singer" starring Al Jolson, was released on October 6, 1927. Within a year of its success, most United States movie theaters had installed sound film equipment. Walt Disney apparently intended to take advantage of this new trend and, arguably, managed to succeed. Most other cartoon studios were still producing silent products and so were unable to effectively act as competition to Disney. As a result, Mickey would soon become the most prominent animated character of the time. Walt Disney soon worked on adding sound to both "Plane Crazy" and "The Gallopin' Gaucho" (which had originally been silent releases) and their new release added to Mickey's success and popularity. A fourth Mickey short, "The Barn Dance", was also put into production; however, Mickey does not actually speak until "The Karnival Kid" in 1929 when his first spoken words were "Hot dogs, Hot dogs!" After "Steamboat Willie" was released, Mickey became a close competitor to Felix the Cat, and his popularity would grow as he was continuously featured in sound cartoons. By 1929, Felix would lose popularity among theater audiences, and Pat Sullivan decided to produce all future Felix cartoons in sound as a result. Unfortunately, audiences did not respond well to Felix's transition to sound and by 1930, Felix had faded from the screen.
Sound film
Parallel with improvements in sound-on-film technology, a number of companies were making progress with systems that recorded movie sound on phonograph discs. In sound-on-disc technology from the era, a phonograph turntable is connected by a mechanical interlock to a specially modified film projector, allowing for synchronization. In 1921, the Photokinema sound-on-disc system developed by Orlando Kellum was employed to add synchronized sound sequences to D. W. Griffith's failed silent film "Dream Street". A love song, performed by star Ralph Graves, was recorded, as was a sequence of live vocal effects. Apparently, dialogue scenes were also recorded, but the results were unsatisfactory and the film was never publicly screened incorporating them. On May 1, 1921, "Dream Street" was re-released, with love song added, at New York City's Town Hall theater, qualifying it—however haphazardly—as the first feature-length film with a live-recorded vocal sequence. There would be no others for more than six years.
In 1925, Sam Warner of Warner Bros., then a small Hollywood studio with big ambitions, saw a demonstration of the Western Electric sound-on-disc system and was sufficiently impressed to persuade his brothers to agree to experiment with using this system at New York's Vitagraph Studios, which they had recently purchased. The tests were convincing to the Warner Brothers, if not to the executives of some other picture companies who witnessed them. Consequently, in April 1926 the Western Electric Company entered into a contract with Warner Brothers and W. J. Rich, a financier, giving them an exclusive license for recording and reproducing sound pictures under the Western Electric system. To exploit this license the Vitaphone Corporation was organized with Samuel L. Warner as its president.
Vitaphone, as this system was now called, was publicly introduced on August 6, 1926, with the premiere of "Don Juan"; the first feature-length movie to employ a synchronized sound system of any type throughout, its soundtrack contained a musical score and added sound effects, but no recorded dialogue—in other words, it had been staged and shot as a silent film. Accompanying "Don Juan", however, were eight shorts of musical performances, mostly classical, as well as a four-minute filmed introduction by Will H. Hays, president of the Motion Picture Association of America, all with live-recorded sound. These were the first true sound films exhibited by a Hollywood studio. Warner Bros.' "The Better 'Ole", technically similar to "Don Juan", followed in October.