In 1940 Walt Disney’s Fantasia was the first film to be released in a multichannel format called Fantasound. Some important innovations are as follows:
- the click track
- dispersion-aligned loudspeaker system with skewed-horn
- the pan-pot
- control-track level-expansion
- overdubbing of orchestral parts
- simultaneous multitrack recording
- and the development of a multichannel surround system.
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