Originally Posted by Davinleeds
Wasn't the center channel born from the video?
No. The centre channel was created specifically for music playback.
A 3-speaker front soundstage dates back to the early 1930s when Bell Labs was experimenting with transitioning from mono to stereo. They found that a minimum of 3 channels/speakers was needed to recreate the wavefront of the original sonic event; anything less being a compromise.
Its first use in film came at the end of that same decade with Walt Disney's 'Fantasia'
, which had a 3-channel soundtrack. Since the film contained practically no dialogue (a couple of lines where conductor Leopold Stokowski greets Mickey Mouse), the centre channel was used primarily for music playback. No different than the way Bell Labs had been using it all along.
There were also some classical recordings done in 3-channel stereo, which had to be down-mixed to 2 channels for release on vinyl records. (Some of those recordings finally got released in their original 3-channel versions on SACD.)
Centre channel use for "video" (i.e., locking the dialogue to the screen) didn't occur till decades after the above events.