Dolby Surround 7.1 adds two new discrete channels to establish four distinct surround zones.
Using these four zones, mixers now can move sounds from the screen to the rear wall behind the audience without using the speakers on the side walls. They can also pull sounds off the screen into the middle of the room without activating the speakers behind the audience. The result: full-featured audio that better matches the visual impact of the picture.
Note: The channels shown in the above images are Left (L), Center (C), Right (R), Left Surround (Ls), Right Surround (Rs), Back Surround Left (Bsl), and Back Surround Right (Bsr).
