Player audio options - bitstream or PCM?

IvanFraser

Member
Question for av enthusiasts:
Do you have any preferences regarding bitstream vs lpcm?
I know it's oft cited that DTSMA and DOLBY TrueHD are mastered for being the same as lossless, but I do hear differences between all 3 on my kit.
I also notice that Steven Wilson 5.1 mixes have the advice to use LPCM for best audio performance, despite using Dolby and DTS HD mixes on his releases. And he's a guy I very much respect.
My av gear will do Dolby TrueHD fine via the dsp on my amp, but DTS gets only humble DTS unless I disable the dsp.
I used the player to convert DTSHDMA to pcm and it sounds fuller, richer and I noticed things I hadn't before.
So, trawling the net for views, I found lots of 'should be the same' comments, but no consensus as to whether people thought LPCM sounds better than bitstream.
Anyone have any preferences?
(Kit includes Panny 820, Panny 900 players, Yamaha 5.1 surround system, hdmi cabled with separate video and audio to tv and amp)
 

gibbsy

Moderator
For multi channel music concerts I prefer the Dolby TrueHD, especially if has an Atmos element if they are all as good as Hans Zimmer Live in Prague. I also stick to the Dolby or DTS option with SD DVDs as well. My Denon X6500 handles the audio and I do prefer it to LPCM. There is such a difference in the quality of soundtracks on concert videos.

With SACD with multi channel having to be passed via HDMI then again that's down to the AV amp to decode. My Pioneer LX500 does have the ability to decode DSD directly to analogue via it's stereo analogue outputs but I never use that because I also have a standalone SACD player. Don't know if you're including SACD in your thread as Panasonics are not UD players.

It's what you like and how your amp and player performs with any format. No right, no wrong.
 

IvanFraser

Member
For multi channel music concerts I prefer the Dolby TrueHD, especially if has an Atmos element if they are all as good as Hans Zimmer Live in Prague. I also stick to the Dolby or DTS option with SD DVDs as well. My Denon X6500 handles the audio and I do prefer it to LPCM. There is such a difference in the quality of soundtracks on concert videos.

With SACD with multi channel having to be passed via HDMI then again that's down to the AV amp to decode. My Pioneer LX500 does have the ability to decode DSD directly to analogue via it's stereo analogue outputs but I never use that because I also have a standalone SACD player. Don't know if you're including SACD in your thread as Panasonics are not UD players.

It's what you like and how your amp and player performs with any format. No right, no wrong.
That Zimmer gig is absolutely outstanding. Love it! I think I last played it with the Dolby. Sadly I don't have any Atmos gear. Video and audio are amazing.
The Pannys will do DSD to pcm, but I prefer to leave that to my stereo kit which can do native dsd. For multichannel DSD I use the pc to 5.1 amp. I have no SACD player.
I'm tending towards the theory of the lpcm being the original and lossless, if present on a disc. Such as with the Steven Wilson 5.1 remixes.
The conversion of DTS to PCM will be down to how well the player does the conversion.
I can't tell whether my amp is sounding 'better' converting DTSMA to PCM, or just 'different'. But the premise that they 'should' be the same is not so on my kit in my ears.
And, ever the pedant, I believe there is a 'right' and 'wrong' when it comes to av, it's preference where right and wrong have no meaning. By that I mean whichever is most accurate to source is 'right' and anything that veers from it is 'wrong' :0)
 

Clem_Dye

Distinguished Member
To me, DTS always sounds better than Dolby, certainly when it comes to the bottom end of things — less flabby. I’ve yet to compare DTS to LPCM, but with so much kit now dropping support for DTS it loks like it’s a choice of LPCM or nothing.
 

goingoingong

Distinguished Member
Isn't this going to come down to the capabilities of the AVR and also the disc itself.

I'll usually use bitstream for movies but with some music concert discs give LPCM a go too. On some discs the DTS HD can be lacking compared to the PCM mixes. I recently noticed Pink Floyd Delicate Touch of Thunder blu-ray had better sound in stereo PCM then upscaled via Auro 2D 5.1 than it does in native DTS HD MA 5.1. With my Rolling Stones concert blu-rays the opposite is true and the DTS HD wins out by having better (more) bass than PCM.
 

IvanFraser

Member
To me, DTS always sounds better than Dolby, certainly when it comes to the bottom end of things — less flabby. I’ve yet to compare DTS to LPCM, but with so much kit now dropping support for DTS it loks like it’s a choice of LPCM or nothing.
I spent a long time years ago when Dolby Digital and DTS became the av formats of choice for digital media, comparing and contrasting on my 5.1 amp. Before I had the 5.1 I had come down firmly in the DTS camp via my stereo kit. For the 5.1 I found the differences less clear and preferred one or the other depending on source.
My old Yamaha defaults to Dolby Digital for its dsp settings (I use one called 'movie') and the DTS can only be activated in non-dsp 'standard' mode. So it made my choice for me for 2 channel stuff. I've used Dolby ever since for tv and Dolby Digital 2 channel.
When it comes to HD versions on blurays I'll go for the Dolby True HD for movies because the amp allows True HD with the movie dsp, but only DTS from the DTSHD. There's no way I can have unprocessed sound for movies in my flat with the wide dynamics inherent in them now. The movie mode adds a slight compression that prevents overly-loud moments, whilst retaining great integrity and dynamics.
For concerts and music I use the ub900 with its superior sound processing and dac. That, I always leave in standard full dynamic range. So I get unfettered Dolby TrueHD or DTSHDMA or LPCM.
And yes, I tend towards the DTS track also if no LPCM. But if the LPCM is there I'll go with that.
Applying the same logic to av audio as to music tracks, I'll always go with the uncompressed or flac or dsd over, say, mp3 if available.
 

IvanFraser

Member
Isn't this going to come down to the capabilities of the AVR and also the disc itself.

I'll usually use bitstream for movies but with some music concert discs give LPCM a go too. On some discs the DTS HD can be lacking compared to the PCM mixes. I recently noticed Pink Floyd Delicate Touch of Thunder blu-ray had better sound in stereo PCM then upscaled via Auro 2D 5.1 than it does in native DTS HD MA 5.1. With my Rolling Stones concert blu-rays the opposite is true and the DTS HD wins out by having better (more) bass than PCM.
And yet, in theory, they should sound the same.
The main question I have is 'which is most accurate to the source' - av capability and personal preference aside? Theoretically, the lpcm should always be the most accurate. As far as I know it's still a standard recording medium, whereas Dolby and DTS are containers; concerts are not recorded in a native dolby or dts format.
If the DTS sounds better, it would be by pure luck, presumably?
 

goingoingong

Distinguished Member
And yet, in theory, they should sound the same.
The main question I have is 'which is most accurate to the source' - av capability and personal preference aside? Theoretically, the lpcm should always be the most accurate. As far as I know it's still a standard recording medium, whereas Dolby and DTS are containers; concerts are not recorded in a native dolby or dts format.
If the DTS sounds better, it would be by pure luck, presumably?
I doubt any concert is put to disc straight from the mic without mixing and mastering of some kind.
So if DTS sounds better it likely has been mixed/mastered better rather than a matter of chance.
 
Dolby TrueHD or DTS MA hands down better for 5.1 +. PCM better for stereo. IMHO.
 
Dolby TrueHD or DTS MA hands down better for 5.1 +. PCM better for stereo. IMHO.
 

IvanFraser

Member
I doubt any concert is put to disc straight from the mic without mixing and mastering of some kind.
So if DTS sounds better it likely has been mixed/mastered better rather than a matter of chance.
Yes, of course mixing and mastering takes place.
I'm assuming that the recording mixing and mastering are going to be done in a lossless recording format. As far as I know, the format used is usually lpcm, then converted to Dolby or DTS.
These formats are not mixes but containers holding the master. So the lpcm will be converted to DTS or Dolby, just as most music is recorded in pcm then for digital media mastered to the cd in pcm, or converted to flac, mp3 etc. for digital distribution.
Hence, the lpcm should always be the superior in theory. The Dolby or DTS master audio should, in theory, be the same as the lpcm once decoded by the AVR.
This is getting to the nub of this. Why would DTSHDMA sound 'better' than the LPCM, if it's a data compression of the LPCM?
 

IvanFraser

Member
Yes, of course mixing and mastering takes place.
I'm assuming that the recording mixing and mastering are going to be done in a lossless recording format. As far as I know, the format used is usually lpcm, then converted to Dolby or DTS.
These formats are not mixes but containers holding the master. So the lpcm will be converted to DTS or Dolby, just as most music is recorded in pcm then for digital media mastered to the cd in pcm, or converted to flac, mp3 etc. for digital distribution.
Hence, the lpcm should always be the superior in theory. The Dolby or DTS master audio should, in theory, be the same as the lpcm once decoded by the AVR.
This is getting to the nub of this. Why would DTSHDMA sound 'better' than the LPCM, if it's a data compression of the LPCM?
When playing Tales From Topographic Oceans yesterday in 5.1, I noted the rate of the LPCM was something like 13.8 mbps, whilst the DTSHDMA was about 9.
And I preferred the LPCM in a simple a-b comparison.
The DTS has to be decoded as a format, whereas the lpcm is the true lossless 'master'.
Please someone educate me if I'm wrong about this :0)
 

IvanFraser

Member
I am aware of the different formats introducing surround effects and height etc. such as Atmos etc. (and I love the DTS HeadphoneX format which enhances stereo to a surround format via headphones).
But surely all of these technologies start with the lpcm master channels?
I'm also aware of the dsd and dxd recording format used in 'audiophile' recordings, many of which are not mixed or mastered, but may use, say, a 1 mic technique or 2 for the likes of binaural. But these recordings are only in the audio formats afaIk.
I'm specifically interested in the application to av where lpcm, dts and dolby options are present for 5.1 mixes.
 

goingoingong

Distinguished Member
Dolby TrueHD or DTS MA hands down better for 5.1 +. PCM better for stereo. IMHO.
Not always. The Delicate Sound of Thunder blu-ray DTS HD 5.1 to me lacks treble, female vocals are too far back in the mix and Dave Gilmour's guitar is lacking high notes. Switch to the stereo PCM track and I find it far better (both in stereo and upmixed/expanded to 5.1 using Auro 2D).
I am aware of the different formats introducing surround effects and height etc. such as Atmos etc. (and I love the DTS HeadphoneX format which enhances stereo to a surround format via headphones).
But surely all of these technologies start with the lpcm master channels?
I'm also aware of the dsd and dxd recording format used in 'audiophile' recordings, many of which are not mixed or mastered, but may use, say, a 1 mic technique or 2 for the likes of binaural. But these recordings are only in the audio formats afaIk.
I'm specifically interested in the application to av where lpcm, dts and dolby options are present for 5.1 mixes.
Aren't they few and far between?
Checking all my concert blu-rays the options are LPCM stereo and DTS HD 5.1.
 

IvanFraser

Member
Not always. The Delicate Sound of Thunder blu-ray DTS HD 5.1 to me lacks treble, female vocals are too far back in the mix and Dave Gilmour's guitar is lacking high notes. Switch to the stereo PCM track and I find it far better (both in stereo and upmixed/expanded to 5.1 using Auro 2D).

Aren't they few and far between?
Checking all my concert blu-rays the options are LPCM stereo and DTS HD 5.1.
Yes, they are limited. The many Steven Wilson 5.1 mixes for Yes, Tull and SW himself are the main ones I have. I noticed that on at least one he says to use lpcm for best quality, which also have the 2 other formats. They also have 96hz 24 bit lpcm stereo mixes.
The 1st Harry Potter BRs did LPCM for lossless with Dolby Digital a long time ago.
Occasionally I come across titles for movies that have LPCM as the alternative to non HD Dolby.
 

IvanFraser

Member
I found a thread discussing the differences here Blu-Rays in LPCM
Seems there are dozens and dozens of brs with lpcm. It is an old thread but I've got quite a few of the discs listed.
Appears to confirm my view on the pcm being closest to the master whilst the dolby and dts are used to compress the original lpcm.
 
 

IvanFraser

Member
I read that before starting this thread.
It's one of the things I alluded to when making the point that these 'lossless' codecs should sound the same. And, as in that article, that has been something oft repeated.
And yet, I can hear a difference on my kit between the compressed and uncompressed formats. Which is what led me to start a discussion to see if others had noticed the same, have any preference, or have any ideas why.
Also, I mentioned the idea of doing the unpacking at the player from bitstream to pcm in order to get this 'identical' pcm prior to the amp doing it. And again, I hear a difference - even on a good player such as the ub900 with a good rep for its audio capabilities.
If there is identical output - as claimed - for all these formats of the same material, why do they all sound different?
CaptainJames, do you have any opinions or preferences?
 
I read that before starting this thread.
It's one of the things I alluded to when making the point that these 'lossless' codecs should sound the same. And, as in that article, that has been something oft repeated.
And yet, I can hear a difference on my kit between the compressed and uncompressed formats. Which is what led me to start a discussion to see if others had noticed the same, have any preference, or have any ideas why.
Also, I mentioned the idea of doing the unpacking at the player from bitstream to pcm in order to get this 'identical' pcm prior to the amp doing it. And again, I hear a difference - even on a good player such as the ub900 with a good rep for its audio capabilities.
If there is identical output - as claimed - for all these formats of the same material, why do they all sound different?
CaptainJames, do you have any opinions or preferences?
As I have said, True HD and DTS MA for multichannel. PCM for stereo.
 

IvanFraser

Member
As I have said, True HD and DTS MA for multichannel. PCM for stereo.
Of course, so you did. Thumps forehead.
I wonder if you've ever played the multichannel as pcm? And if so, is there a difference on the ub9000?
That's one of the best specced br players for audio, so should output the dolby or dts masters as pcm with no discernible difference, allegedly.
 

goingoingong

Distinguished Member
Of course, so you did. Thumps forehead.
I wonder if you've ever played the multichannel as pcm? And if so, is there a difference on the ub9000?
That's one of the best specced br players for audio, so should output the dolby or dts masters as pcm with no discernible difference, allegedly.
For stereo PCM with UB9000 the best output would be 2ch analogue due to the AK4493 DAC. That is better spec'd than the AK4490 DAC in my Denon X8500 or the AK4458 in the rest of the Denon/Marantz range.
 
Of course, so you did. Thumps forehead.
I wonder if you've ever played the multichannel as pcm? And if so, is there a difference on the ub9000?
That's one of the best specced br players for audio, so should output the dolby or dts masters as pcm with no discernible difference, allegedly.
No, all multichannel discs are bitstreamed. No Atmos with PCM.
 

IvanFraser

Member
No, all multichannel discs are bitstreamed. No Atmos with PCM.
Have you ever toggled between Dolby TrueHD and DTS Master Audio tracks on a disc and noticed a preference for one or the other?
I wasn't aware that Atmos will not be converted to pcm by the 9000.
 

IvanFraser

Member
For stereo PCM with UB9000 the best output would be 2ch analogue due to the AK4493 DAC. That is better spec'd than the AK4490 DAC in my Denon X8500 or the AK4458 in the rest of the Denon/Marantz range.
I've no doubts that's right. I play my stereo hd tracks as pcm from the 900 to my headphone kit and the quality is superb. I imagine an even better result from the 9000. Unlike the pcm analogue from the 820 which is clearly inferior to the 900.
I would be interested to know if the surround sound output as pcm - with the player doing the conversion - from the hd dolby and dts is up to that level, or whether it sounds lesser than the original bitstream with the amp doing the conversion.
On the 900, to me, there's a difference. As for preference, I would say I would struggle as to which sounds 'best'. The 9000, being such a high end player, I would love to think would unpack the track to pcm very well, and as such may be more faithful to the original master than allowing my amp to do it; an amp that's quite old and only just had the DTSHD capability (and 3d pass through) which was fairly new at the time I bought it.
 

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