Dolby Pro Logic IIx is an extension of Dolby Pro Logic II technology. This
sophisticated algorithm processes native stereo- and 5.1-channel material
to produce 6.1 or 7.1 output channels. Dolby Pro Logic IIx expands choice in
playback system configuration (allowing
5.1
,
6.1, or
7.1 playback channels) and, when
incorporated into an audio/video (AV) receiver or processor it allows a
convenient upgrade path from a traditional 5.1-channel sound system to 7.1
output
channels.
[Source:
Dolby
Technologies]