M-AUDIO Sonica Theater - Manual (Page 19)

4.0 - This signal is the same as 4.1 (description following), only without the
subwoofer channel.
4.1 - This is how most feature films from 1970-1980 were mixed. It will play
back from the left, center and right speakers with a mono signal going to
all of the surrounds. An additional “point one” signal gets sent to the
subwoofer in all of the following formats, called .1 because it only uses up
1/10th of the data of the other channels.
5.0 - This signal is the same as 5.1 (description following), only without the
subwoofer channel.
5.1 - This is how most current DVDs are released. Dolby Digital® and
DTS® soundtracks can have up to 5.1 channels.This signal plays back from
the left, center, and right speakers, plus two surrounds, left and right.
19