Why cant PS3 bitstream HD audio?

LMDavies

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As I understand it, the PS3 cannot bitstream the HD formats via HDMI and never will! It can bitstream DD/DTS via HDMI so why can't it bitstream TrueHD and DTS MA without some firmware update? What is the technical reason behind this?
 
Apparently it's because the chip that handles HDMI in the PS3 isn't capable of transmitting it:
Particular HDMI 1.3 chip in PS3 cannot pass TrueHD/DTS-HDMA bitstream

It doesn't matter anyway, just let the PS3 decode it and send PCM to your amp. Decoding is decoding - you get the same result whether it's done by the amp, by the PS3 or by a little pixie who lives in the cable.
 
Thanks Nelviticus. If bitstreaming does not matter. How do you explain why my old Tosh XE1 and current Pio BDP-51FD's sound alot better (much more bass /louder) when bitstreamed to my amp compared to the PS3's LPCM?

Apparently it's because the chip that handles HDMI in the PS3 isn't capable of transmitting it:
Particular HDMI 1.3 chip in PS3 cannot pass TrueHD/DTS-HDMA bitstream

It doesn't matter anyway, just let the PS3 decode it and send PCM to your amp. Decoding is decoding - you get the same result whether it's done by the amp, by the PS3 or by a little pixie who lives in the cable.
 
As far as I am concerned there is an audible difference between the decoding done in a high quality AV amp than what is done by the PS3.
 
If bitstreaming does not matter. How do you explain why my old Tosh XE1 and current Pio BDP-51FD's sound alot better (much more bass /louder) when bitstreamed to my amp compared to the PS3's LPCM?

As far as I am concerned there is an audible difference between the decoding done in a high quality AV amp than what is done by the PS3.

Well Dolby TrueHD and DTS-HD Master Audio are both lossless CODECS which means that when you decode their signal you get out exactly what was put in. Whether the PS3 decodes it or the amp decodes it they will both end up with exactly the same data. 'Quality' doesn't come into it - a device either decodes it correctly or doesn't decode it at all. It's a bit like opening ZIP files - you can open them with WinZip, 7-Zip or Windows' built-in Compressed Folders explorer but you always get the same results.

So why does it sound different? I would guess at one of four answers (please bear in mind these are guesses):

1) It doesn't sound different, you just think it does. Human senses can be pretty subjective. If you put the same jam in two different jars, one with a label saying 'finest luxury jam' and the other saying 'no frills basic jam', then do a public taste test, I bet most people will say the 'luxury' one tastes best.

2) You may have set it up wrong - maybe you're not actually sending LPCM HD audio from your PS3.

3) Your amp is applying one sound processing mode to the PS3's signal and is applying a different one to the other signal, so you really are hearing different results.

4) I am just a random 'bloke on the internet' who doesn't know what he's talking about, but talks about it with an air of great authority.

Pick one!
 
Thanks Nelviticus - Option 3 applies to me..

"Your amp is applying one sound processing mode to the PS3's signal and is applying a different one to the other signal, so you really are hearing different results."

Reason why is because my Pioneer LX70 amp briefly displays +4db when bitstreaming and there is more bass. It may just be louder but to my ears it sounds better and I prefer it to LPCM.
 
There is a difference. It's to do with the digital to analogue conversion process. The DACs in the high end amps are better than the decoding that the PS3 can provide.

This argument that lossless is lossless no matter where the decoding is done is clearly incorrect. By the same logic, all CD players would sound the same as they all decode lossless red book audio. Clearly not true.
 
There is a difference. It's to do with the digital to analogue conversion process. The DACs in the high end amps are better than the decoding that the PS3 can provide.

This argument that lossless is lossless no matter where the decoding is done is clearly incorrect. By the same logic, all CD players would sound the same as they all decode lossless red book audio. Clearly not true.

what do digital to analogue convertors have to do with it? whether the ps3 decodes the Compressed audio or the amp does, it still passes through the same DAC's in the amp (LPCM is digital!).

there are two possibilities - either the ps3 is doing exactly what it should be, or the amp is. which is right i dont know, but i know my ps3 in LPCM provides no shortage of bass, thats for sure. it could be that the amp's are decoding with the LFE channel 10db hotter - try turning the LFE channel up by 10db then compare the ps3's output (to the amp doing the decoding with the LFE at normal levels)
 
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There is a difference. It's to do with the digital to analogue conversion process. The DACs in the high end amps are better than the decoding that the PS3 can provide.

This argument that lossless is lossless no matter where the decoding is done is clearly incorrect. By the same logic, all CD players would sound the same as they all decode lossless red book audio. Clearly not true.

A DAC is a Digital to Analog Converter. When the PS3 sends LPCM to the amp it's not doing any digital to analog conversion - it's decoding a digital package and sending a digital signal: digital to digital. The DACs in the amp then convert it to the analog signal needed by the amplification circuits (or by the speakers if you have a digital amp).

So whether your source (PS3 or other Blu-Ray player) sends LPCM or bitstream, the only DACs involved are ones in the amp.

Don't confuse decoding with conversion. DACs don't decode, they convert something that's already been decoded.

As for CDs, a lot of CD players use(d) analog outputs so they normally do use DACs. I'm guessing that the DACs aren't involved if you use a CD player's digital output (and by the same token the PS3's DAC's are involved if you use its analog outputs, but this topic is about DTS-MA and Dolby-HD, not stereo) in which case any difference in players is down to things like how good their error correction is.
 
Well Dolby TrueHD and DTS-HD Master Audio are both lossless CODECS which means that when you decode their signal you get out exactly what was put in. Whether the PS3 decodes it or the amp decodes it they will both end up with exactly the same data. 'Quality' doesn't come into it - a device either decodes it correctly or doesn't decode it at all. It's a bit like opening ZIP files - you can open them with WinZip, 7-Zip or Windows' built-in Compressed Folders explorer but you always get the same results.

So why does it sound different? I would guess at one of four answers (please bear in mind these are guesses):

1) It doesn't sound different, you just think it does. Human senses can be pretty subjective. If you put the same jam in two different jars, one with a label saying 'finest luxury jam' and the other saying 'no frills basic jam', then do a public taste test, I bet most people will say the 'luxury' one tastes best.

2) You may have set it up wrong - maybe you're not actually sending LPCM HD audio from your PS3.

3) Your amp is applying one sound processing mode to the PS3's signal and is applying a different one to the other signal, so you really are hearing different results.

4) I am just a random 'bloke on the internet' who doesn't know what he's talking about, but talks about it with an air of great authority.

Pick one!


My post said as far as i'm concerned. I didnt say that would be the same for everyone, Just my personal view.

Apologies if what I said was wrong in your eyes, but everyone has the right to their point of view without being ridiculed.
 
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My post said as far as i'm concerned. I didnt say that would be the same for everyone, Just my personal view.

Apologies if what I said was wrong in your eyes, but everyone has the right to their point of view without being ridiculed.

Hold yer horses there! The post 'Nelviticus' made was both informative and humble. I saw no trace of ridicule.

That he took the time to explain how you may be mistaken in a friendly and helpful manner demands your respect, not your reproach or a defensive stance. :lesson:
 
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My limited understanding of this bistream v PCM quality discussion is that the two should in theory sound identical.
In reality, LPCM is prone to jitter within the HDMI interface and as a result the bistreamed version can sound a tad tighter.

Anything more than that is either the amp's different handling of each format (e.g. making one sound louder than the other, or applying different DSP mode to each format) or simply placebo.

They're both still digital though, so as has been previously said DAC's have naff all to do with it.
 
Hold yer horses there! The post 'nelviticus' made was both informative and humble. I saw no trace of ridicule.

That he took the time to explain how you may be mistaken in a friendly and helpful manner demands your respect, not your reproach or a defensive stance. :lesson:

correctified ( ;) ), and + 1 :thumbsup:

they were very helpful and informative posts, not condescending, malicious, or patronising in any way imho. :smashin:
 
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Chaps on the PS3 sound output for HDMI do I tick all the boxes for LPCM etc or just some of them?

Thanks.
 
i just ran the auto test and then unticked everything that said 7.1
 
correctified ( ;) ), and + 1 :thumbsup:

they were very helpful and informative posts, not condescending, malicious, or patronising in any way imho. :smashin:

:oops: I was obviously sleeeeeeepy there. Thanks for the correction, I've edited my post accordingly :thumbsup:
 
4) I am just a random 'bloke on the internet' who doesn't know what he's talking about, but talks about it with an air of great authority.

Pick one!


That the particular sniping comment I was referring to.
 
Rob, apologies for any offence caused. The "I" in no.4 was meant to refer to me - as in, "Nelviticus is just a random bloke on the internet" etc. etc.

I know a little bit about digital compression (I'm a computer programmer), a little bit about electronics (I studied it at college) and a little bit about home cinema and high-def sound formats (I'm an enthusiast and read about it in magazines and on AVForums). So, although I know a little bit about what I'm talking about I could still be wrong so don't take my word for it.

That's what I meant, sorry if it came across as rude.
 
it isnt rude to be right and its even better when your not pious about it you were being humble and honest and apparently right from my limited understanding of this:smashin:
 
Rob, apologies for any offence caused. The "I" in no.4 was meant to refer to me - as in, "Nelviticus is just a random bloke on the internet" etc. etc.

I know a little bit about digital compression (I'm a computer programmer), a little bit about electronics (I studied it at college) and a little bit about home cinema and high-def sound formats (I'm an enthusiast and read about it in magazines and on AVForums). So, although I know a little bit about what I'm talking about I could still be wrong so don't take my word for it.

That's what I meant, sorry if it came across as rude.

I'm sorry. I misunderstood what you meant. No harm done :)
 
Surely the kit has something to do with the output of sound quality.

Im not disputing that you may be right in what you say about uncompressed sound being the same wether its bitstream or LPCM to the amp. However if this was the case then all amps would sound the same which they dont.

I am in the corner of that I think my Blu Ray player sounds alot better with HD formats than the PS3. I have compared them both at same speaker set up settings and there is a clear difference to me between the 2.
The sound field is more alive from the BR player and punchier in places. Now Im not saying the PS3 is a total shod at what it does far from it, but the player to me does sound better.

If there is no difference then why do we spend small fortunes on better amps and players.
I also can tell a huge difference between playing CDs in the PS3 and a CD player.

Personelly I believe like all things digital it depends on how the kit decodes the files, I beleive my amp will decode the sound formats better than my PS3 and Blu Ray player hence the amp does the work.
 

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