Bitstream vs. Linear PCM

Originally Posted by ase8776

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).

Originally Posted by Mickaelmc

wow.
Depending on which Thread I look at.. it's either bitstream is better or Linear PCM.

Can anyone give me the best answer?

I have a PS3. I use it for mostly regular DVD's...and right now just a few Blu-Ray titles.
I have a Denon AVR-4800 receiver. (It's about 7 or 8 years old now)
It doesn't have HDMI, so I have the audio hooked up via Optical wire.

Which should I have my settings at? Linear PCM or bitstream?

Originally Posted by ikecomp

I have a question with regards to PCM vs Bitstream. My receiver can only do 2 channels of PCM (even over HDMI) and I recently found out that the movie SWAT has a 5.1 PCM track and no legacy tracks like DD or DTS. My question is how would I set up my PS3 to get some form of 5.1 sound out of it going into my receiver? Would I simply changing the audio output on the PS3 to bit stream or pcm remedy this?

Originally Posted by ikecomp

I have a question with regards to PCM vs Bitstream. My receiver can only do 2 channels of PCM (even over HDMI) and I recently found out that the movie SWAT has a 5.1 PCM track and no legacy tracks like DD or DTS. My question is how would I set up my PS3 to get some form of 5.1 sound out of it going into my receiver? Would I simply changing the audio output on the PS3 to bitstream or pcm remedy this?

Originally Posted by thebigdaddye

well since your receiver can only do 2 channel pcm it will not process it that way. your probably better off going bit stream and letting the receiver process it that way. the way to do this without changing the setting on the ps3 is during the start of the movie hit the triangle button to bring up the on screen dvd/blu ray settings. then go to the far right and look for a symbol that looks a little like an oval with lines through it and hit x. next skip over the noise reduction ect.. setting and go to the bottom to the audio output setting and hit x and move it to bit stream if it's on pcm and then back out and play the movie and it should be good to go. i do this for my dvd's because they don't have pcm tracks just DD and dts tracks so it's a lot easier to do it that way then on the ps3 setting menu. oh course this will not work if your receiver doesn't do dd or dts ,but i assume yours does hope this helps

Ouch. I'm not sure there is a fix for that one. I don't believe the PS3, or any player, can actually do DD or DTS encoding on-the-fly, so I can't see any way for the PS3 to produce a 5.1 output stream that the receiver can handle.

The receiver should be advertising its capabilities to the PS3 over HDMI, so the PS3 should know to downmix to 2.0 PCM when its in PCM output mode. What happens if you set it to bitstream? I would imagine that either the PS3 would see that the receiver's not capable of receiving the 5.1 PCM and refuse to send it, or the receiver itself would fail to receive the bitstream. Do you get any sound at all with bitstream?

Originally Posted by chartwel

linear pcm if you want uncompressed audio. bitstream if you want regular Dolby digital.

seriously, if you want uncompressed audio, go with pcm. not everything has this, but its worth it if it does. just played some folklore in uncompressed, and man, it has some good sound.

Originally Posted by Mickaelmc

wow.
Depending on which Thread I look at.. it's either bitstream is better or Linear PCM.

Can anyone give me the best answer?

I have a PS3. I use it for mostly regular DVD's...and right now just a few Blu-Ray titles.
I have a Denon AVR-4800 receiver. (It's about 7 or 8 years old now)
It doesn't have HDMI, so I have the audio hooked up via Optical wire.

Which should I have my settings at? Linear PCM or bitstream?

Originally Posted by Mickaelmc

Ok. I'm not sure if anyone knows anything about my receiver. It's a Denon AVR-4800 THX Ultra Surround EX receiver that requires a second amplifier if I wanted 7.1 surround sound. This was a $2000 amp 10 years ago.

So... Could I get an additional 2-channel amp with HDMI, and somehow get the Lossless audio sound?

typically DD double digital which is sent bit stream is around 600 kb and pcm loss less is usually sent around 5.0+ mbs . the pcm track will be much clearer and more i guess defined when compared to double digital,

Originally Posted by Dixie Flatline

The question is really about audio output modes on the PS3, not the audio formats on the disc. The audio track on the disc is either Linear PCM or a compressed format (which can be lossy, like DD/DTS, or lossless, like DD TrueHD or DTS-MA).

If you set the PS3 to output bitstream, then it will send exactly what's on the disc without modifying it at all, and it's up to your receiver to decode whatever needs decoding. If the PS3 is set to output PCM, then it will decode compressed formats into Linear PCM and send that LPCM stream to the receiver.

When you've selected a PCM soundtrack from the disc, then the PS3 will be sending PCM to the receiver regardless of the setting. However, as mentioned above, if the PS3 is set to bitstream then it won't be able to make any changes to the audio stream, such as mixing in menu sounds.

At this point, there's really no reason to select bitstream output on the PS3 unless your receiver has problems receiving multichannel PCM via HDMI. The PS3 is perfectly capable of decoding any of the available audio formats except DTS-MA (which is currently neither decoded nor passed as bitstream), and you get the ability for it to mix in additional audio.

The BD format is really designed for the player to do audio decoding anyway; the ability to pass the HD audio formats (DD TrueHD and DTS-MA) as bitstream to the receiver, which requires HDMI 1.3, is something that was demanded by the receiver manufacturers so that they could badge their receivers as "True-HD Capable" and "DTS-MA Capable". In reality, any receiver that can receive multichannel PCM over HDMI is capable of playing these formats, as long as the player does the decoding, which is what they're designed to do.

Originally Posted by benso37

So, even though my receiver (Onkyo 605) can decode the DTS-MA codec, the PS3 cannot get it to the receiver?

Why does everyone want the PS3 to pass the sound bitstream if L-PCM is better?

Originally Posted by Dixie Flatline

As I understand it, the PS3 currently does not pass DTS-MA as bitstream over HDMI. There's been some discussion here that suggests the current models of PS3 may never do so, as the HDMI 1.3 transceiver chips used in the current models are very early production models which do not implement the ability to pass HD audio formats as bitstream (which as an optional part of the HDMI 1.3 spec). However, nobody seems to know for sure.

I think in the case of DTS-MA, no one knows when the PS3's getting the ability to decode it internally, so that's why they're hoping for the ability to pass it as bitstream to a receiver like the 605 that can decode it.

Originally Posted by UxiSXRD

PCM. There is simply no advantage to having an AVR decode over the player.