Classical Hollywood cinema
The beginning of the sound era itself is ambiguously defined. To some, it began with "The Jazz Singer", which was released in 1927 and increased box-office profits for films, as sound was introduced to feature films. To others, the era began in 1929, when the silent age had definitively ended. Most Hollywood pictures from the late 1920s to 1960s adhered closely to a genre—Western, slapstick comedy, musical, animated cartoon, and biopic (biographical picture)—and the same creative teams often worked on films made by the same studio. For instance, Cedric Gibbons and Herbert Stothart always worked on MGM films; Alfred Newman worked at Twentieth Century Fox for twenty years; Cecil B. DeMille's films were almost all made at Paramount Pictures; and director Henry King's films were mostly made for Twentieth Century Fox. Similarly, actors were mostly contract players. Film historians and critics note that it took about a decade for films to adapt to sound and return to the level of artistic quality of the silents, which it did in the late 1930s.
Sound film
In 1913, Edison introduced a new cylinder-based synch-sound apparatus known, just like his 1895 system, as the Kinetophone; instead of films being shown to individual viewers in the Kinetoscope cabinet, they were now projected onto a screen. The phonograph was connected by an intricate arrangement of pulleys to the film projector, allowing—under ideal conditions—for synchronization. However, conditions were rarely ideal, and the new, improved Kinetophone was retired after little more than a year. By the mid-1910s, the groundswell in commercial sound motion picture exhibition had subsided. Beginning in 1914, "The Photo-Drama of Creation", promoting Jehovah's Witnesses' conception of mankind's genesis, was screened around the United States: eight hours worth of projected visuals involving both slides and live action were synchronized with separately recorded lectures and musical performances played back on phonograph.