Brandon, although Dolby doesn't make it mandatory, most(all?)receivers that have DPLII include the three adjustment parameters: Center Width, Panorama and Dimension. The width adjustment varies the way material which is about equal in strength in the two front channels is distributed; either keeping it all in the front speakers(i.e., a "phantom center" effect), sending it all to the center speaker, or a mixture of the two. Panorama(which I don't use)actually just sends some of the in-phase sound from the front channels to the surrounds, creating an effect part way toward all-channel stereo. It's the Dimension control which varies the amount of out-of-phase material present in the front channels which is extracted and sent to the surrounds; to a limited extent this can increase the surround effect with material which has a relatively small amount of surround ambience mixed into the front channels.
