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General discussion

Dolby Digital vs. Pro Logic II?

May 29, 2008 9:10AM PDT

I am playing a Blu-Ray DVD, the audio is Dolby Digital 5.1. My receiver, a Pioneer VSX-918V-K, does not read the audio as Dolby Digital. Instead, it is reading it as Pro Logic II. I understand Pro Logic II is a lower standard than Dolby Digital. Any idea why my Pioneer receiver is not reading and playing the audio in Dolby Digital? Have tried playing with the settings and no luck.

Discussion is locked

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AFAIK
May 29, 2008 9:28AM PDT

its not a lower standard. Its a matrixing algorithm. You are just fine, unless you want to matrix some rear speakers (6.1, 7.1) for which you will need PLiiX.

DD can be mono, AFAIK. 2.0, all the way up to 5.1.

However, I don't remember the last time I listened to DD, let alone DTS. By far, most of my HT enjoyment is with lossless codecs. Ok, there are a few that are DD+, but I think those are only HD-DVD within my colletion.

If your BDP, which you never named, is a BD-30, you cannot access the lossless audio since your Pio does not have the decoders. If you have a PS3, you should definitely be accessing them. Unless its one of those few models that only do video pass-thru with HDMi. I hate those receivers. Whats the point...

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Ok
May 29, 2008 1:35PM PDT

Well how is it hooked up? RCA red and white cable, digital coax, or optical.

if it is digital coax or optical, then this is right so now youll need to go into the setup menu of the blu ray player and change the audio settings to Dolby digital or bit stream.

good luck
Gabe

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ok
Jun 1, 2008 1:33AM PDT

gabereyes is correct. Do get DD you will need to hook it up with a digital cable of some sort whether it be optical or digital coax. A lot of people think hooking it up with the red and white composite cables will give them surround sound. Sure it may play through all 5 speakers but your only getting left and right channel. If you hook it up with optical or Digital coax you will get left right front back and LFE for the subwoofer. Once you hook it up with a digital cable make sure and set your receiver to Dolby digital and not pro-logic. In short Prologic simulates surround sound for people who don't or cant use digital cables.

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Kitten
Jun 1, 2008 6:56AM PDT

I get what you are saying. However, let's straighten out some things just for the heck of it.

DD can totally be mono. Sure, you are RIGHT that for a DISCRETE 5.1 you will need at least SPDIF. But, again, DD can be 1.0 mono. DD is a series (selection) of lossy formats. Ok...

Prologic 1 is different than PLii which is different from PLiiX. These are not just for people without discrete surround my friend. People use the latest iteration to matrix rear channels from 5.1.

Just to make things clear. Happy

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Ok
Jun 1, 2008 1:38PM PDT

I not understanding what you are trying to say about Pro logic.

To me its a fake version of 5.1 like Neo 6 or logic 7, I would never use it, I would only listen to any audio in the original form DD, DTS, and/or Stereo.

the same goes so stereo I wouldnt use theater, hall, or the old school phantom processing.

please help me understand here, im a little lost in what your trying to say.

thanks
gabe

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sure thing Gabe
Jun 1, 2008 2:51PM PDT

I understand your aversion to matrixing. For me.. I only have two speakers for stereo anyways. Wink But some people really like Logic7.

Ok... I should have been more specific than I was.

People use PliiX even with a discrete 5.1 track to matrix the rears in order to get 6.1 or 7.1.

There was actually a poll once at AVS between who enjoys using the matrix function for 5.1 sources.

There are a few who are extremely knowledgable there about this stuff. The first person who comes to mind is sdurani. Try searching his posts with pertinent keywords. He's involved in sort of movie club among AVS members, but Im scared to join them. They Know Too Much!!! Waaaay too much...

anyways, matrixing is not to be sneezed at. Sure, tastes are paramount, and you have yours. But the technology is more advanced than one might immediately think.

I matrix all movie soundtracks for the rears.

pro logic, and PL ii are both pretty out-dated. you'll only see the "X" version in any modern receiver now.

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oh ok
Jun 2, 2008 1:15PM PDT

you just taking about the 6th and 7th channels of the surround sound being matrixed in a 5.1 sound track.

I thought you were talking about something else, I have an older 6.1 reciever and it doesnt do that, the model the year after did, but not mine.

anyways I didnt find very many DVD's recorded in DTS ES or DD EX so I unhooked my rear speaker about 3 years ago and its been in storage ever sence, plus it was just one to many speakers in my small living room. lol

Gabe