Sound film
The primary steps in the commercialization of sound cinema were taken in the mid- to late 1920s. At first, the sound films which included 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, which was at the time the leading brand of sound-on-disc technology. Sound-on-film, however, would soon become the standard for talking pictures.
Once Upon a Time in the West
Except for about a minute of the "Judgment" motif, before Harmonica kills the three outlaws, no soundtrack music is played until at the end of the second scene, when Henry Fonda makes his first entry. During the beginning of the film, Leone instead uses a number of "natural sounds", for instance a turning wheel in the wind, sound of a train, grasshoppers, shotguns while hunting, wings of pigeons, etc., in addition to the diegetic sound of the harmonica.