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Ok i had the original PS3 and this was going into my Arcam AV888 now when playing a Blu-Ray film or concert i was listing to the sound track as LPCM and i thought it was amazing but now i have the new PS3 Slim and those same films are in glorious bitstream.
I really do feel that the sound is better, there is always a debate about LPCM and bitstream but for me i do feel i hear the difference.

I would love to know what you guys think on this "smoke and mirrors" or real upgrade ??
 

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My understanding is that bitstream is untouched digital directly from the disc and does not get altered by the PS3. LPCM If I'm not mistaken does get altered by the DACs in the PS3 so in your case the Arcam has better DACs and is handling it better.
 

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From other findings I believe LPCM offers higher levels of jitter over HDMI also, but as Tony has said the DAC's in the AV888 are rather good so no suprise really, it has always been my opinion that Dolby True HD and DTS HD MA is better handled by the receiver anyway, now if we are talking SACD and DVD-Audio that may not always be the case depending on the player....
 

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I dont know if things have changed, but the PS3 in will only bitstream DD 5.1, for HD audio it has to be set to LPCM. In LPCM mode the player is decoding the soundtrack, while in bitstream the processor its being sent to decodes it.

I stand to be corrected if an update fixed this, but if it has I missed it. If the new one does indeed bitstream HD content, it stands to reason a good high end Receiver will be better at decoding the content than the PS3 for me, and I have no problem believing in your experience.
 

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Going from bitstream to LPCM should have nothing to do with the DACs. DAC stands for Digital to Analog Converter. Both Bitstream and LPCM are digital. Now, if you're talking about running analog multich, that's a whole other ball of cables...
As a general rule, I prefer to advise bitstream whenever it's possible, as some AVRs/Processors won't provide bass management on LPCM (and definitely not on analog multi) and many players don't offer as many bass management options as most AVRs.
I don't know about the jitter, but I would think that the two forms should be very nearly identical. That being said, I'll allow that I don't know about different decoders (not the same as DACs) so I suppose one device could do the decoding better than another one, it just would be news to me.
 

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The signal does go through a DAC as the amps in the receiver are not digital they require an analog signal.
 

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The signal does go through a DAC as the amps in the receiver are not digital they require an analog signal.
This occurs after the processing though, once the signal is decoded, its then fed through the DAC to get to the speakers. As such I wouldnt consider the DAC an effective component of the decoding process.

Unless I'm mistaken of course, gotta have the obligatory disclaimer :D

I was taking part in a fair bit of discussion on what is the best decoder in any given system, but finding that will be hard, it was some time ago.
 

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Your both correct in that manor, I think its more just what does a better job of decoding the signal.
 

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Going from bitstream to LPCM should have nothing to do with the DACs. DAC stands for Digital to Analog Converter. Both Bitstream and LPCM are digital. Now, if you're talking about running analog multich, that's a whole other ball of cables...
As a general rule, I prefer to advise bitstream whenever it's possible, as some AVRs/Processors won't provide bass management on LPCM (and definitely not on analog multi) and many players don't offer as many bass management options as most AVRs.
I don't know about the jitter, but I would think that the two forms should be very nearly identical. That being said, I'll allow that I don't know about different decoders (not the same as DACs) so I suppose one device could do the decoding better than another one, it just would be news to me.
Ive never really experienced any jitter over LPCM so tat ones news to me. I suppose the digital nature of the decoding process should mean it makes no difference what does the decoding, but perhaps processing power has some effect on reliability. I would have thought though that different manufacturers have different ideas on how is best to go about decoding, and there in would lie the differences. I would have thought they would be quite subtle though.
 

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Your both correct in that manor, I think its more just what does a better job of decoding the signal.
I think we need to find some documentation of some testing between different decoders. Of course something like this is difficult and needs controlled conditions to remove as many variables as possible. Room and speakers should all be the same. Any applied room eq should remain the same and ideally not be employed at all, meaning an anechoic chambers is really the ideal.

Dyhon has proved an excellent source of white papers, I'll PM him to see if he can help.
 

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Hmmm... preemptive strike... well played... I was going to nominate you to do the research!
Let us know what David says.
 

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It would be good to see some solid data on conversion of the signal into LPCM in players over the conversion in the amps being done and jitter levels, but surely that will also depend on the equipment used, as Pioneer uses PQLS to combat jitter and Arcam have employed some clever re clocking to eliminate it on there equipment.
 

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David did reply to my PM, but unfortunately this isnt his area of expertise.

I dont think the actual transmission of data is going to be the big difference here, although that said, I would think bitstream should be easier to transmit as its basically the compressed data as its stored on the disc rather than decompressed data. Surely the compressed data is less load heavy, which is possibly why jitter occurs in LPCM transmissions. I would have thought HDMI 1.3/4 could handle the load though, anyone got any ideas on that?

I'm trying really hard to think of where there could be real differences between the two, but the whole idea of digital is that everything is very clinical, accurate and correct, and the processing is merely a function that happens and is completed. The DAC shouldnt be an issue as its the final stage of everything getting to your speakers, and however the signal is decoded, it then passes through the same DAC to your speakers, and strictly speaking the theory is the decoded digital signal should come out of the processor identically every time.

The biggest area I can imagine differences might occur is in the actual processing of the decoded digital information. Which in my meagre grey matter leads me to only one conclusion, the processing is where the differences lie, and ideally one would aim to use the highest quality piece of processing equipment in their set up. I'm also fairly confident that most mid to high end AVR's should do this better than the PS3, but I have no data to back any of this up and this is basically me sounding out how I think the whole issue stands.

I'll get on with some intensive googling when I have a bit of free time, and see what I can come up with.
 

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The only formal comparisons of data conversion I have ever read have been those done by manufacturers, and invariably their studies are skewed so that whatever product or methodology they are promoting looks good. Audioholics may have done something like this in the past, but often those articles are more based in opinion and the old "objectivist VS subjectivist" circular arguments.

I'll look around and see if I have anything on this in the archives. :)
 

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Cheers David.

I have a feeling this one is always going to be in the eye of the beholder though. Ive been through this 3 times now with no definitive answer ever even being got close too..
 

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Hello,
The LPCM versus Bitstream debate has been a contentious one on certain Forums. Personally, I have found better performance having my AVR doing the decoding of the lossless codecs. And given the HDMI jitter levels with Onkyo being quite high, it would give creedence to my personal experience. Arcam and Pioneer SC AVR's have quite low HDMI jitter for what its worth.

While some believe it to be a placebo and that people just like seeing True HD and DTS HD appear on the Display of their AVR's, it has been my experience that they sound better bitstreamed.

With the original PS3, that was the one thing many of us speculated and hoped for the possibility of having that ability. It was later shown to be a hardware incompatibility that kept the 1st gen PS3 from offering bitstreaming.
Cheers,
JJ
 

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I dont know if things have changed, but the PS3 in will only bitstream DD 5.1, for HD audio it has to be set to LPCM. In LPCM mode the player is decoding the soundtrack, while in bitstream the processor its being sent to decodes it.

I stand to be corrected if an update fixed this, but if it has I missed it. If the new one does indeed bitstream HD content, it stands to reason a good high end Receiver will be better at decoding the content than the PS3 for me, and I have no problem believing in your experience.
The new PS3 slims will bitstream the new HD 7.1 audio, and let your AVR decode it. I had my friend bring his over, just so I could see the little blue light finally come on, on my AVR.
 

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Yes this subject has been discussed to death on many forums but I am also of the opinion that I prefer the decoding to be done in the AV amp as I believe it does give a better sound and have always felt that way, since my first Onkyo amp.

Hello,
The LPCM versus Bitstream debate has been a contentious one on certain Forums. Personally, I have found better performance having my AVR doing the decoding of the lossless codecs. And given the HDMI jitter levels with Onkyo being quite high, it would give creedence to my personal experience. Arcam and Pioneer SC AVR's have quite low HDMI jitter for what its worth.

While some believe it to be a placebo and that people just like seeing True HD and DTS HD appear on the Display of their AVR's, it has been my experience that they sound better bitstreamed.

With the original PS3, that was the one thing many of us speculated and hoped for the possibility of having that ability. It was later shown to be a hardware incompatibility that kept the 1st gen PS3 from offering bitstreaming.
Cheers,
JJ
 

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Elite Shackster
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And given the HDMI jitter levels with Onkyo being quite high
I have to say Ive never noticed any jitter with my PS3 and Onkyo with LPCM. Is there something I should look out for?

The new PS3 slims will bitstream the new HD 7.1 audio, and let your AVR decode it. I had my friend bring his over, just so I could see the little blue light finally come on, on my AVR.
Sweet, now all I need to do is convince my brother to swap PS3's with me :T
 
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