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#1 ·
The title says it all..

What exactly is the difference between Bitstream vs. Linear PCM? ... the two options you have to choose from when choosing HDMI Audio Out from the settings. What exactly do I need to choose in order for the sound to come out the way it should? Does Linear PCM need to be chosen in order for PCM soundtracks from a blu-ray disc to output at its optimum?


When I play Pursuit of Happyness in 5.1 PCM (Bitstream enabled), my receiver will show that PCM is active. When I play it in 5.1 English (Bitstream enabled), my receiver will whos that Dolby Digital is active. But the 5.1 English sounds louder than the 5.1 PCM. But shouldn't that be the other way around... 5.1 PCM is uncompressed. When I play both soundtracks with Linear PCM enabled, my receiver will only show PCM active (even if I play the 5.1 English soundtrack).


Any help is appreciated.


Thanks
 
#53 ·
I just picked up Ratatouille on Blu-ray and notice on the back audio section that this film can out 5.1 Dolby Digital and 5.1 Uncompressed 48bit/24 sound. How can I decode that on my receiver. I use Bitstream and have my PS3 hooked up via HDMI to my receiver. My receiver has these capabilities.

Thanks
 
#54 ·

Quote:
Originally Posted by kingnothing123 /forum/post/12205461


I just picked up Ratatouille on Blu-ray and notice on the back audio section that this film can out 5.1 Dolby Digital and 5.1 Uncompressed 48bit/24 sound. How can I decode that on my receiver. I use Bitstream and have my PS3 hooked up via HDMI to my receiver. My receiver has these capabilities.

Thanks

It's one or the other. Uncompressed doesnt need decoding by the AVR. You choose it from either the audio option on the BD or press triangle during playback and choose PCM track.
 
#55 ·

Quote:
Originally Posted by Marc Alexander /forum/post/12165156


I am sorry if I wasn't clear in my post. Bitstream seems to be more dynamic after level matching.


I am powering the surround speakers via the Yamaha and the front stage with an external amp, so I doubt I'm running out of headroom when level matching.


I can't explain why, but Bitstream seems to be the preferred choice [for me at least].

This is the same thing I am experiencing. I can hear that the pcm maybe could sound better, but it is unbalanced, and the bass is lacking.
 
#57 ·

Quote:
Originally Posted by Neilster /forum/post/12207470


This is the same thing I am experiencing. I can hear that the pcm maybe could sound better, but it is unbalanced, and the bass is lacking.

One hypothesis I plan to explore:


The Yamaha RX-V1600 has two bass management memories AFAIK. One global memory, and a seperate one for the multi-channel analog input. I'm wondering if the multi-channel analog memory also applies to multi-channel PCM via HDMI. Or, if there is a third memory for multi-channel PCM via HDMI. Time to dust the SPL meter out and do some testing. I'll report back once I get the chance to test.
 
#59 ·

Quote:
Originally Posted by kingnothing123 /forum/post/12205461


I just picked up Ratatouille on Blu-ray and notice on the back audio section that this film can out 5.1 Dolby Digital and 5.1 Uncompressed 48bit/24 sound. How can I decode that on my receiver. I use Bitstream and have my PS3 hooked up via HDMI to my receiver. My receiver has these capabilities.

Thanks

Set the HDMI audio out setting to PCM, not bitstream. The PS3 will then send the uncompressed 5.1 PCM to your receiver via HDMI.
 
#63 ·
Let me make a chart for the lossless audio sources.

BITSTREAM MODE (HDMI OUT)

--------------------------------


5.1 LPCM passed to AV receiver untouched for DAC = YES

5.1 Dolby TrueHD passed to AV receiver untouched for decoding & DAC = NO

5.1 DTS-HD Master Audio passed to AV receiver untouched for decoding & DAC= NO



LPCM MODE (HDMI OUT)

--------------------------


5.1 LPCM passed to AV receiver untouched for DAC = YES

5.1 Dolby TrueHD decoded & passed to AV receiver for DAC = YES

5.1 DTS-HD Master Audio decoded & passed to AV receiver for DAC = NO



EDIT: DAC = Digital to Analog Conversion


EDIT2: Most of us are hoping Sony will release a firmware to change all the NO answers to YES answers.
 
#64 ·
^^The debate continues though which is actually better. I had no idea the PS3 passed 5.1 DD trueHD by Bitstream. I just run it all LPCM over HDMI. My Denon 4308 receiver doesn't show DD True HD since I am doing PCM, but it sure sound way better and the bit rate is where it should be.
 
#65 ·

Quote:
Originally Posted by Hughmc /forum/post/12220276


^^The debate continues though which is actually better. I had no idea the PS3 passed 5.1 DD trueHD by Bitstream. I just run it all LPCM over HDMI. My Denon 4308 receiver doesn't show DD True HD since I am doing PCM, but it sure sound way better and the bit rate is where it should be.

The PS3 does not "pass" Dolby TrueHD via Bitstream for your AV receiver to decode and then convert to analog. Hopefully it will in the future.


When the PS3 is in LPCM mode, the PS3 first "decodes" Dolby TrueHD and *then* passes the resulting LPCM to your AV receiver to be changed to analog for your speakers.
 
#66 ·

Quote:
Originally Posted by mike_j_johnson /forum/post/12220010


Let me make a chart for the lossless audio sources.

BITSTREAM MODE (HDMI OUT)

--------------------------------


5.1 LPCM passed to AV receiver untouched for DAC = YES

5.1 Dolby TrueHD passed to AV receiver untouched for decoding & DAC = NO

5.1 DTS-HD Master Audio passed to AV receiver untouched for decoding & DAC= NO



LPCM MODE (HDMI OUT)

--------------------------


5.1 LPCM passed to AV receiver untouched for DAC = YES

5.1 Dolby TrueHD decoded & passed to AV receiver for DAC = YES

5.1 DTS-HD Master Audio decoded & passed to AV receiver for DAC = NO



EDIT: DAC = Digital to Analog Conversion


EDIT2: Most of us are hoping Sony will release a firmware to change all the NO answers to YES answers.

This should be put somewhere for all to see, it would save a lot of questions that pop up everyday about what to set the PS3 to
 
#67 ·
For BluRay movies if I select LPCM on my PS3 via HDMI what should these setting be on the Onkyo TX-SR674 sub-menu with a 7.1 configuration to get the best sound including the subwoofer?


I have the following categories & choices.


Ana/PCM - Direct, Stereo, Mono, PL IIx movie-game-music & so on through all the DTS stuff


MCH PCM - Direct & Multich


MCH Ana - Direct & Multich


PCM192k - Direct & Stereo
 
#68 ·
For people who have 5.1 receivers with no HDMI, do you keep your PS3 set to Bitstream or LPCM? I have PLII on my receiver, so I think that the uncompressed tracks sound better in fake surround than the DD track, even if I am sacrificing some specificity in the sound field. But I don't know if it makes any difference whether I have the PS3 set to Bitstream or LPCM so I've been switching back and forth depending on whether I listen to a DD track or an uncompressed track. What settings do y'all use? Does it make any difference?
 
#69 ·

Quote:
Originally Posted by Bryan_P /forum/post/12678433


For people who have 5.1 receivers with no HDMI, do you keep your PS3 set to Bitstream or LPCM? I have PLII on my receiver, so I think that the uncompressed tracks sound better in fake surround than the DD track, even if I am sacrificing some specificity in the sound field. But I don't know if it makes any difference whether I have the PS3 set to Bitstream or LPCM so I've been switching back and forth depending on whether I listen to a DD track or an uncompressed track. What settings do y'all use? Does it make any difference?

I just got an 80 GB PS3 and am in a similar situation (my AVR is non-HDMI and supports DD and DTS over optical). I did some A/B comparisons with 2 films (Casino Royale - 5.1 PCM) and (Die Hard 4 - DTS MA). I found the following:


1. For Casino Royale, I prefered the 5.1 PCM track down-converted to 2 channel PCM w. Dolby Pro Logic applied. I found that the increased dynamic range and overall sound quality overcame the benefit of having more discrete channel separation via DD 5.1.


2. Die Hard 4's DTS MA soundtrack includes a 1.5 Mps 5.1 "Core" track that can be passed over optical. I found this to provide excellent dynamic range and overall quality.


So my conclusion is that for Dolby TrueHD and PCM tracks, I will have the PS3 downrez to 2 channel LPCM. For movies containing DTS MA (Fox, NewLine), I will switch over to Bitstream output.


I think alot of this will come down to personal taste. Many on this forum argue that 640 kps Dolby Digital (included on most every BR disc) is more than good enough to their ears.
 
#70 ·

Quote:
Originally Posted by bchalmers /forum/post/12679811


I just got an 80 GB PS3 and am in a similar situation (my AVR is non-HDMI and supports DD and DTS over optical). I did some A/B comparisons with 2 films (Casino Royale - 5.1 PCM) and (Die Hard 4 - DTS MA). I found the following:


1. For Casino Royale, I prefered the 5.1 PCM track down-converted to 2 channel PCM w. Dolby Pro Logic applied. I found that the increased dynamic range and overall sound quality overcame the benefit of having more discrete channel separation via DD 5.1.


2. Die Hard 4's DTS MA soundtrack includes a 1.5 Mps 5.1 "Core" track that can be passed over optical. I found this to provide excellent dynamic range and overall quality.


So my conclusion is that for Dolby TrueHD and PCM tracks, I will have the PS3 downrez to 2 channel LPCM. For movies containing DTS MA (Fox, NewLine), I will switch over to Bitstream output.


I think alot of this will come down to personal taste. Many on this forum argue that 640 kps Dolby Digital (included on most every BR disc) is more than good enough to their ears.

Good post, thanks for the input!
 
#71 ·
hey guys, a question here...


with linear pcm, if the signal on the disc is 5.1, and my receiver is 7.1, I've noticed my two rear speakers aren't being used, and my receiver(onkyo 605) doesn't give me any options to change that. With bitstream, I get the icon(dts in this case), and I can then use neo:6 to matrix it to 7...


does this sound right? Should the linear pcm signal be 7 channels if it's only a 5.1 on the disc, or is there a way to get it to?
 
#72 ·

Quote:
Originally Posted by Tread /forum/post/13028191


hey guys, a question here...


with linear pcm, if the signal on the disc is 5.1, and my receiver is 7.1, I've noticed my two rear speakers aren't being used, and my receiver(onkyo 605) doesn't give me any options to change that. With bitstream, I get the icon(dts in this case), and I can then use neo:6 to matrix it to 7...


does this sound right? Should the linear pcm signal be 7 channels if it's only a 5.1 on the disc, or is there a way to get it to?

The issue's with the 605. It can't matrix LPCM.
 
#73 ·

Quote:
Originally Posted by bchalmers /forum/post/12679811



I think alot of this will come down to personal taste. Many on this forum argue that 640 kps Dolby Digital (included on most every BR disc) is more than good enough to their ears.

I dont know about that. Maybe to those who havent heard an uncompressed HD track. DD 640 may very well be good enough. But once you have heard the two back to back..there is no comparison. I compared the 640 DD to Dolby True HD track on Dave Matthews and Tim Reynolds last night. Night and day difference.
 
#74 ·
Bitstream versus Linear PCM

The PS3 provides options for either "Bitstream" or "Linear PCM" when outputing the audio signal. This option is located in the "Settings->BD/DVD Settings->BD/DVD Audio Output Format(HDMI)" and "Settings->BD/DVD Settings->BD Audio Output Format (Optical)" settings of your XMB. Linear PCM is audio data that is not encoded (nor compressed) and is in it's pure digital form, ready for conversion into analog for the speakers. A regular CD stores all its songs in Linear PCM form. Most audio starting with the DVD store digital data encoded and compressed (like Dolby Digital or DTS Digital Surround). If "Bitstream" option is selected, the PS3 will take this undecoded and uncompressed audio and send it untouched to the HDMI or TOSLINK cable for your external decoder to decode. In other words, the receiver at the other end of the HDMI or TOSLINK must have special chips that can decode and uncompress formats like Dolby Digital and DTS Digital Surround, and then convert the resultant Linear PCM to analog (via a DAC) for the speakers connected to the external decoder. If "Linear PCM" option is selected, the PS3 will actually decode the audio into Linear PCM first, before sending it to the HDMI or TOSLINK. In this case the receiver on the other end of the HDMI or TOSLINK only needs to convert the Linear PCM to analog for the speakers connected to it. Because of the current bandwidth limitations of TOSLINK, choosing Linear PCM (the decoded and uncompressed signal) on this connection limits you to only two channels of audio. For multichannel (like 5.1) over TOSLINK, you must use "bitstream", which uses smaller bandwidth of compressed and encoded data.
 
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