Dolby Help II (1 Viewer)

[Eddie Ras]

ok,

i've read everything, but it still doesn't answer the bulk of my questions.

if a movie is listed as DOLBY, does that mean it's surround or 5.1?? how do you know?

what about regular HBO movies, without the dolby symbol? do these sound different than the ones that state dolby?

are they surround?

finally, my receiver has prologic II- but i have yet to see it as one of my choices when i change the input- isn't II an updated version of regular pro logic? i see pro logic as one of my choices, but not II.

any/all help would be greatly appreciated!!

ps

i have direct tv with a dolby digital receiver

 

[Seth Paxton]

Listed where? Do you mean on a DVD box or a film on DirecTV?
Few of the DirecTV channels are in Dolby Digital but when they are the header should state so explicitly (the info header that comes up for a channel).
Some of the PPV channels are in Dolby Digital alond with Starz East. Many of the others are hit and miss.
There is Dolby Surround, Pro-Logic, Pro-Logic 2. Then there is Dolby Digital.
Here is the tricky part. Dolby Digital really just means a compression technique for digital sound data to make it take less space. Basically a STORAGE METHOD.
However it's normal use with 5.1 tracks is sort of tying it to that meaning unintentionally. Dolby Digital can be used for a 1.0, 2.0, 3.1, 4.0, 5.0, 5.1 track for example.
So a 1.0 track means a sound signal intended only for ONE SPEAKER (the center). By default this is obviously MONO.
But with 2.0 tracks they could be 2 speaker MONO (same sound from the L/R speaker rather than using the middle...for more fullness to the mono track basically), 2 speaker stereo (like a music concert), or 2 channel PRO-LOGIC (meaning a left and right signal that will be used to create the Pro-Logic center and surround signal).
BUT, you could also have a 5.1 do the same thing yet by-pass the Pro-Logic decoding, meaning that it would have the same signal in both rear channels and a center signal that would be what Pro-Logic would produce...but why do that when you can just store 2.0 and let the receiver do the rest.
Normally 5.1 means unique signals to all 5 speakers and the subwoofer.
Okay, to make the point more about the compression being seperate from the surround aspect - CDs are PCM (digital samples but uncompressed). With DVD-Audio players you can have 5.1 PCM. The digital connection can't handle the bandwidth for this thus the need for a DVD-A player and analog connections for all 5.1 channels to a receiver that has inputs for them.
I have an Olivia Newton-John DVD-A disc with this PCM 5.1.
PCM is BETTER than DTS or Dolby Digital because it is uncompressed. However, for 5.1 it's usually not an option due to the STORAGE SPACE required.
However, many LDs and some DVDs do use 2.0 PCM which is also better than Dolby Digital 2.0. This 2.0 PCM can also be 2 speaker mono, stereo or Pro-Logic. Do the Right Thing Criterion DVD has a PCM 2.0 Pro-Logic track on it, for example, so you don't get the compression effects on the Pro-Logic track.
If you are looking at a DVD it should say so on the box, using the channel grid picture to show what type of DD or DTS tracks it has (or even PCM). By the way, PCM tracks become more important when buying CONCERT DVDs. A DD 5.1 and a PCM stereo track is what I would call the best standard set of tracks for concert DVDs.
I don't have a Pro-Logic 2 receiver and haven't followed it enough to help on that aspect. Also, this probably didn't answer everything but hopefully whittled it down a bit. I watch for other questions.

 

[Seth Paxton]

Oh, yeah, most of the stuff coming down on HBO, etc that isn't DD 5.1 will be 2 channel digital intended for Pro-Logic decoding.

Since you have a DD DSS receiver you should be getting a digital audio signal all the time now, just not 5.1 very often. Mostly you are getting PCM Pro-Logic stuff.

 

[Jimmy P]

Not all movies broadcast by HBO on Direct TV are broadcast in Dolby Digital,usually before the the movie it will say what sound format it will be in ie: stereo,surround,Dolby Digital 5.1 or alt audio.Yes Pro Logic II is a dramatically improved, updated matrix surround system, it offers enhanced sound with a full-range stereo surround output and a greatly improved steering logic, resulting in high channel separation. All Pro Logic II receivers offer a Movie mode optimized for movies or programs with Dolby Surround soundtracks. This mode is also appropriate for use with video games. Movie mode retains the important features of Pro Logic, but with a full-bandwidth stereo surround output, the listening experience is much closer to the sound you get from Dolby Digital.

 

[Michael Reuben]

if a movie is listed as DOLBY, does that mean it's surround or 5.1?? how do you know?

If you've read the materials at Dolby's site, then you should know that the name "Dolby" refers to many different products and sound formats. Focusing on whether the name "Dolby" does or doesn't appear someplace won't get you meaningful answers. You have to focus on the source medium.
Take HBO broadcasts, for example. It doesn't matter what sound format is listed on the movie. What matters is how you receive your HBO signal and what sound format is used by that service. Analog cable? You're probably getting a 2-channel analog signal that may (or may not) give you a surround mix when played through the proper equipment. Statellite or digital cable? You're probably getting a Dolby Digital 2.0 track that can be decoded for surround, and you may be getting a DD 5.1 track depending on (a) whether HBO happens to be sending out such a signal for that program, and (b) whether your cable or satellite company is transmitting it.
M.

 

[Eddie Ras]

You're probably getting a Dolby Digital 2.0 track that can be decoded for surround, and you may be getting a DD 5.1 track depending on (a) whether HBO happens to be sending out such a signal for that program, and (b) whether your cable or satellite company is transmitting it.

so what you're saying is that there is no way to tell ahead of time what you're getting.

and seeing "dolby" on a satellite broadcast only tells that it's one of the many formats that i read about- be it 1.0, 2.0, 4.1, 5.1 etc...

so i guess i shouldn't worry about finding shows in 5.1! if they're there i'll know it!

 

[Michael Reuben]

so i guess i shouldn't worry about finding shows in 5.1! if they're there i'll know it!

That's pretty much my approach. I recently upgraded to digital cable, and I have to rely on my DD decoder to tell me what type of signal I'm getting from channel to channel.

M.