Kevin C Brown
Senior HTF Member
- Joined
- Aug 3, 2000
- Messages
- 5,726
I thought I knew the answers to these, but maybe not:
1) What does a (THX) Surround EX (or DTS-ES matrix) decoder do with the out of phase material sent to the rear L + R speakers?
Or...
2) Could it be, that for DVDs mastered for (THX) Surround EX/DTS-ES matrix, that there is specifically no appreciable out of phase material sent to the rears? We all know that the in-phase material ends up in the rear center channel.
I'm asking because some people use (THX) Surround EX/DTS-ES matrix modes on "std" DD/DTS DVDs. Seems to me, that this would "throw away" the out-of-phase material that may accidentally be present there.
I'm also asking in the context of a DIY 6.1 set up:
If I apply *straight* Dolby Pro Logic decoding to the rears on any of (THX) Surround EX/DTS-ES matrix/DD/DTS material, the out of phase material is gone. But maybe it's not present in the (THX) Surround EX/DTS-ES matrix material to begin with! So you *shouldn't* use straight DPL decoding back there for "std" DD/DTS because you might be losing some info from the L + rears.
But I recently came across an older DPL processor that specifically includes a "Dolby 3 Channel" mode. This mode specifically decodes Dolby Surround soundtracks (2 channel) to only the front 3 channels (which, on a DIY 6.1, would be the 3 rears). It specifically "folds" the out of phase material into the fronts (or in reality, the backs).
Does that make sense?
------------------
1) What does a (THX) Surround EX (or DTS-ES matrix) decoder do with the out of phase material sent to the rear L + R speakers?
Or...
2) Could it be, that for DVDs mastered for (THX) Surround EX/DTS-ES matrix, that there is specifically no appreciable out of phase material sent to the rears? We all know that the in-phase material ends up in the rear center channel.
I'm asking because some people use (THX) Surround EX/DTS-ES matrix modes on "std" DD/DTS DVDs. Seems to me, that this would "throw away" the out-of-phase material that may accidentally be present there.
I'm also asking in the context of a DIY 6.1 set up:
If I apply *straight* Dolby Pro Logic decoding to the rears on any of (THX) Surround EX/DTS-ES matrix/DD/DTS material, the out of phase material is gone. But maybe it's not present in the (THX) Surround EX/DTS-ES matrix material to begin with! So you *shouldn't* use straight DPL decoding back there for "std" DD/DTS because you might be losing some info from the L + rears.
But I recently came across an older DPL processor that specifically includes a "Dolby 3 Channel" mode. This mode specifically decodes Dolby Surround soundtracks (2 channel) to only the front 3 channels (which, on a DIY 6.1, would be the 3 rears). It specifically "folds" the out of phase material into the fronts (or in reality, the backs).
Does that make sense?
------------------