1K Club - QQ Shooting Star
- May 30, 2005
- Kansas City
Larry might have something more specific in mind but when I read a comment like that I think it refers to the problem of side imaging for all quad/surround formats that use Pair Wise Mixing as the source. It only works for center front.Side imaging problem?
Using the front speakers or stereo only speakers as a pair if Left = Right then you should get a very distinct center front image. As its been remarked on the forum by myself & others there are times listening to 4.0 that the phantom center front is so specific you have to get up & put your ear to center front speaker to make sure it's not on! A friend of mine with really nice Thiel speakers the imaging is even better. A vocalist not only comes from the middle but is so specific it seems to have a height & finite distance away. Like you could get up & touch the singers nose.
If you try PWM for center left where Lf=Lb you get a very strong left side impression but it is very broad with no really specific localized sound from the middle of the speakers. Same problem with center back where Lb=Rb. You get a definite "behind you" effect but again it is broad left/right not specific center back.
That doesn't mean you can't hear center side or rear. If you were facing forward & someone was standing exactly to your left side talking, it would be quite precise. Same thing if they stood directly behind you & were talking. So the problem isn't with our hearing just PWM 4.0 doesn't work perfect for all directions.
The only solution I know of is to use real speaker locations to the sides such as in 7.1 ch theater systems and with a dedicated center back. ATMOS might bring something of a solution to side imaging as well. Of course Ambisonics purported to have all this corner/side/height thing figured out years ago.