How was the sound added to the film?

Answer 1

A sound film is a motion picture with synchronized sound, or sound technologically coupled to image, as opposed to a silent film. The first known public exhibition of projected sound films took place in Paris in 1900, but decades would pass before sound motion pictures were made commercially practical. Reliable synchronization was difficult to achieve with the early sound-on-disc systems, and amplification and recording quality were also inadequate. Innovations in sound-on-film led to the first commercial screening of short motion picturesusing the technology, which took place in New York City in April 1923.

The primary steps in the commercialization of sound cinema were taken in the United States in the mid- to late 1920s. At first, the sound films incorporating synchronized dialogue---known as "talking pictures", or "talkies"---were exclusively shorts; the earliest feature-length movies with recorded sound included only music and effects. The first feature film originally presented as a talkie was The Jazz Singer, released in October 1927. A major hit, it was made with Vitaphone, the leading brand of sound-on-disc technology. Sound-on-film, however, would soon become the standard for talking pictures.

By the early 1930s, the talkies were a global phenomenon. In the United States, they helped secure Hollywood's position as one of the world's most powerful cultural/commercial systems (see Cinema of the United States). In Europe (and, to a lesser degree, elsewhere) the new development was treated with suspicion by many filmmakers and critics, who worried that a focus on dialogue would subvert the unique aesthetic virtues of soundless cinema. In Japan, where the popular film tradition integrated silent movie and live vocal performance, talking pictures were slow to take root. In India, sound was the transformative element that led to the rapid expansion of the nation's film industry---the most productive such industry in the world since the early 1960s.