Basic principles of projection

Part three : Sound systems

As techniques develop and get more sophisticated the quality of projection and the sound reproduction improves. In a certain way one could say that history is repeating itself. Cinema sound was introduced in the '20s by means of a long play record, while todays newest sound carrier is again an off-line device : the CD. Different systems are used for synchronizing sound and motion. The latest technique provides the best quality and is called "Digital sound".

Famous KLANGFILM EUROPE optical sound head

On this page an overview of the systems available (or known to me)

1. Silent movies
   
   Live orchestra
   Phonograph of Mr Edison
   
2. Gramophone
   
   more or less synchronous sound became possible
   Vitaphone by Western Electric
   The Jazz Singer produced by Warner Bros. (1927)
   
3. Synchrone sound, sound track printed of film strip next to image
   
   Optical
   
   Chronology of the history of optical sound recording, to 1953
   Longitudonal system
   Amplitude system
   Stereo (Fantasia by Walt Disney)
   Perspecta sound by MGM
   Dolby sound system
   THX system ( Star Wars - George Lucas)
   
   Magnetic sound
   
   One channel
   Four channels Cinemascope
   Six channels 70mm film Todd AO
   
   Digital sound
   
   CD rom synchronized by optical marks on the film strip.
   DTS
   SRD