soundfilm

Soundfilm refers to motion pictures that include synchronized sound along with the picture. The term covers both sound-on-film systems, where the audio track is recorded directly on the film, and sound-on-disc systems, where a separate disc carries the audio synchronized to projection.

Early experiments in the 1910s and 1920s produced several methods for pairing sound and image. Lee de Forest's Phonofilm (1923–25) used sound-on-film; Western Electric's Vitaphone used sound-on-disc; Fox's Movietone used sound-on-film. These approaches aimed to provide dialogue, music, and effects synchronized with the moving image.

The Jazz Singer (1927) demonstrated synchronized sound for a feature-length film using Vitaphone; its popularity accelerated the transition from silent to sound film. Although not the first talkie, it popularized the new technology and led studios to adopt sound-wide.

In the late 1920s and early 1930s, sound-on-film became dominant; technical features included optical soundtracks and standardization around 24 frames per second. Musicals and dialogue-driven narratives became common, while silent filmmaking gradually declined and audiences adjusted to the new medium.

The advent of sound film transformed filmmaking in many ways, demanding new equipment, soundproof stages, and changes in acting, directing, and production workflows. Later developments added improvements in audio quality, stereo and multi-channel formats, and eventually digital sound, but the core concept—synchronized sound accompanying moving images—remains the defining feature of soundfilm.