Yamaha DDP-10 Owner's Manual page 9

Dolby Digital (AC-3) + 2 Digital Sound Fields
Digital sound fields are created on the independent left and
right surround sides of the Dolby Digital (AC-3) decoded sound
field respectively. They create a wide acoustic environment and
emphasize surround-effect in the room, letting you feel much
presence as if you are watching a movie in a popular Dolby Stereo
Digital theater.
This combination is available on the sound field program
" DIGITAL ENHANCED".
Dolby Digital (AC-3) + 3 Digital Sound Fields
Digital sound fields are created on the presence side and the
independent left and right surround sides of the Dolby Digital (AC-
3) decoded sound field respectively. They create a wide acoustic
environment and much surround effect in the room without losing
high channel separation. With wide dynamic range of Dolby Digital
(AC-3) sound, this sound field combination lets you feel as if you
are watching a movie in the newest Dolby Stereo Digital theater.
This will be the most ideal home theater sound at the present time.
This combination is available on the sound field program
"DIGITAL MOVIE THEATER".
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