What is Dolby® Surround Pro Logic®?

Dolby® Surround Pro Logic® — Soundtrack is 4 channels of audio information - left, centre, right and surround matrix, encoded into 2 audio tracks. These 2 tracks are then carried on stereo program sources such as videotapes and TV broadcasts into the home, where they can be decoded to recreate the original 4 channels and the surround experience.