Originally posted by paule123
Tonight I was checking OTA vs. cable, and the Grammys were coming in Dolby ProLogic II via the SA8000HD cable box (Wide Open West), but on my Samsung SIR-T165 OTA, I was getting simple "stereo". Weird???
As a side note, this is the first broadcast I have heard truly good surround with Dolby PLII, all others have been very lame compared to Fox's DD5.1....
Dolby ProLogic is
just a stereo signal. ProLogic just uses ambience information in the regular two-channel feed to decode the surround information. And, yes, because it uses this technique, it rarely sounds anywhere near as good as full Dolby Digital. For that matter, ProLogic will extract some surround information from any stereo feed - even one that has no DPL encoding at all.
I'm not aware of any way for a receiver to "detect" ProLogic - generally, it is used only when the user turns it on. So my guess is that you have it turned on for the input that accepts your cable box, but not on the input that accepts your OTA receiver.
As for the Grammy video, I was disappointed, too. Some of the problems in the video may be Adelphia's and/or CBS's, but some seem to be inherent in digital video broadcast. For example, some of those strobing effects - you can't change that much of the screen with that rapidity without triggering pixelization. Even at the highest bandwidths allowable on the air, you're going to see pixelization. So television producers are going to have to learn how to work in the digital broadcast world. On an event that is produced specifically for television, they should be able to avoid effects that trigger broadcast problems like these.