• We’re currently investigating an issue related to the forum theme and styling that is impacting page layout and visual formatting. The problem has been identified, and we are actively working on a resolution. There is no impact to user data or functionality, this is strictly a front-end display issue. We’ll post an update once the fix has been deployed. Thanks for your patience while we get this sorted.

Hey I thought HDTV had Dolby Digital 5.1 sound??

UNCjigga

UNCjigga

Lifer
What gives?? Just got our HDTV cable/tuner setup today (actually I just finished watching 'The Handler' on CBS in HDTV!) We have a coax digital audio cable going from the cable tuner to our Dolby Digital/DTS receiver. The receiver is the kind that can autosense the signal and switch appropriately between stereo, pro-logic, Dolby Digital and DTS. However, I noticed that none of the HDTV programming I sampled had 5.1 audio. The receiver would say 'Dolby Digital 2.0' (regular stereo) and 'Dolby Digital 3.1' (stereo, center channel and LFE/subwoofer.) Is there no 5.1 audio on HDTV...or is something wrong with my setup (no options to change it in cable box setup)...or is something wrong with our local affiliates?

Also, how the heck am I supposed to tell if something is broadcast in 1080i or 720p??
 
Only some broadcasts have 5.1...just all HD is in DD. THere should be a functin of your tv that shows what mode it is running in.
 
Originally posted by: MCrusty
Only some broadcasts have 5.1...just all HD is in DD. THere should be a functin of your tv that shows what mode it is running in.
Click to expand...

IIRC some abc shows are in DD5.1. i know that last year's grammy presentation by cbs was in 5.1, and some movies on abc are 5.1 too. hbo defintely has 5.1. the hd/digital spec does not require DD to be broadcast along with the the video.
 
Originally posted by: GOSHARKS
the hd/digital spec does not require DD to be broadcast along with the the video.
Click to expand...

Yes, the spec does require Dolby Digital. It just doesn't specify which channel arrangement. Technically, a Dolby Digital soundstream can have any arrangement 1-6 speakers with or without a subwoofer. I think it may be going up to 7 in the near future?
 
Originally posted by: Goosemaster
DTS cannot travel over coaxial if I remember correctly. It needs the bandwidth of Fiber(toslink/Optical)
Click to expand...

No, DTS can travel over digital coax or SPDIF.
 
Originally posted by: TerryMathews
Originally posted by: GOSHARKS
the hd/digital spec does not require DD to be broadcast along with the the video.
Click to expand...

Yes, the spec does require Dolby Digital. It just doesn't specify which channel arrangement. Technically, a Dolby Digital soundstream can have any arrangement 1-6 speakers with or without a subwoofer. I think it may be going up to 7 in the near future?
Click to expand...

i just know that our receiver shows prologic if it isnt DD5.1, but you are correct.
http://electronics.howstuffworks.com/hdtv1.htm
 
Check out HBO or Cinemax in HD, most movies should come through in 5.1. HBO will tell you as the movie is coming on whether it's 5.1.
 
lol i just wanted to thank all of you of this topic for opening my eyes


i also had thought digital audio can only travel over TOSLINK until reading this....

now i realized it travels over digital coax too! and i found a spot on my hdtv box and reciever that are both for digital coax....and i had thought i had no more room!!!


i just bought a 10 dollar coax digital cable off ebay!!!
THANKS EVERYONE! LOL
 
Originally posted by: GOSHARKS
i just know that our receiver shows prologic if it isnt DD5.1, but you are correct.
Click to expand...

Most receivers -- including yours, apparently -- will automatically enable one of the matrix decoders (Prologic, Prologic II, Logic 7, etc) on top of the Dolby Digital decoder if the DD bitstream contains only one or two channels. In these cases, the 2-channel DD bitstream is treated the same as a 2-channel analog input -- which makes sense.
 
Originally posted by: skriefal
Most receivers -- including yours, apparently -- will automatically enable one of the matrix decoders (Prologic, Prologic II, Logic 7, etc) on top of the Dolby Digital decoder if the DD bitstream contains only one or two channels. In these cases, the 2-channel DD bitstream is treated the same as a 2-channel analog input -- which makes sense.
Click to expand...

There is a flag in the DD stream for whether or not to enable Prologic. I'd have to go through my movie collection, but I've got a movie that def. does not enable ProLogic, and it's DD2.0.

Basically, everyone these days enables ProLogic decoding because it's pretty good when the system is set up right. But it is a setting.
 
Ok, there is definitely some confusion here and I can understand.

There are a number of different Dolby formats all encopassed by the "Dolby Digital" label.

The one used the most these days for HDTV is "2.0 Stereo". This allows you to use your Pro-Logic II decoder to process the signal with surround. 2.1 is the same thing with the LFE channel.

Most "Pro-Logic II" receivers will not allow you to process a DD 5.1, 5.0, 4.1, 4.0, 4.1, 4.0, 3.1, 3.0, 2.0 mono (left+right mono), 1.0 mono (never saw a 1.1 broadcast) which is out of the center channel.

I'm not even going to get into DD/DTS EX-ES and DTS 96/24. 😉

Your receiver/processor might have its own sound imaging modes that will work on various DD and DTS formats. YMMV.
 
You must log in or register to reply here.

TRENDING THREADS

Back
Top