Lead: Making pictures talk, putting sound with film, took decades to develop. It required a whole new kind of technology.

Intro. : A Moment in Time with Dan Roberts.

Content: The problem was synchronization and sound quality. Essayist Curt Wohleber writes that even if an inventor could have gotten lips to synch with pictures of the person speaking, turn of the century sound reproduction was so bad that it would have ruined the effect. Yet, by 1910, the tools were in place which would ultimately solve the problem. Alexander Graham Bell and his telephone had demonstrated that sound could be converted into an electric signal. Then Lee de Forest developed the audion, a vacuum tube that amplified and manipulated recorded sound. By 1920 De Forest had developed a new system, which converted sound into light. Processed by an audion, light was shined through a thin slit and recorded on the movie film at the exactly the right time, therefore speaking lips fit with spoken words.

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