Hello Sidereal,
Your DVD player's "dialog enhancer" function that mixes the dialog into both speakers in a stereo setup works very well so long as you sit exactly on-axis between your main speakers. If you move to the left or the right, or if someone else is viewing the movie and sitting to one side (off-axis), then the dialog will collapse to the left or right speaker, whichever is closer to you or the off-axis viewer.
This is the intrinsic flaw of stereo. Virtually all vocal pop, jazz and rock recordings (not operas) are mixed with the vocals pan-potted to the center, which is great if you are sitting midway between the front speakers. When you move to the left or right of the room, the stereo image largely collapses, and the vocal shifts to the speaker nearest you.
Yes, a center-channel speaker "localizes" the dialog--indeed anchors it--to the center speaker, just as it does in a movie theater, to the center speaker behind the screen. If it didn't do that, half the audience to the left or right of the theater would hear the dialog coming from the left or right side of the screen, respectively. No good.
So, here's the trick. Locate your center as close as possible to your TV screen. If it's more than 2 feet away, the dialog may seem disembodied from the actors on-screen.
Independently adjust the center-channel volume, so you get a natural mix of the dialog with the stereo left-right music and effects. That's a huge advantage of having a dedicated center-channel speaker. You can control the mix--of dialog vs. music and effects. You can't do that with your DVD player's "center-channel enhancer".
I even tweak the center-channel balance of singers when I play back stereo vocal CDs or opera CDs in Pro LogicII or H/K's Logic7 (or dts's Neo6).
Regards,
