Player audio options - bitstream or 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.
Nothing to do with the player, PCM can't convey Atmos metadata.

I've also never come across a Blu ray that has both Dolby True HD and DTS MA tracks - you only get one or the other.
 

IvanFraser

Member
Nothing to do with the player, PCM can't convey Atmos metadata.

I've also never come across a Blu ray that has both Dolby True HD and DTS MA tracks - you only get one or the other.
Ok. So presumably if you set your player to output pcm, it would simply default to the 7.1 setup derived from the TrueHD pattern and ignore the heights.
I'm sure I have several with both dolby and dts options. But I think that some have the dts for 5.1 and also Dolby for Atmos, which is in 7.1 when played on non-Atmos kit to TrueHD. On my kit the 7.1 is muxed to 5.1.
Could explain some of the differences in sound quality I noticed on the few times I've toggled them in the past.
I always check out the audio setup before playing but tend just to leave the Dolby TrueHD on if given a choice, unless presented with 5.1 lpcm also.
 

gibbsy

Moderator
Ok. So presumably if you set your player to output pcm, it would simply default to the 7.1 setup derived from the TrueHD pattern and ignore the heights.
I'm sure I have several with both dolby and dts options. But I think that some have the dts for 5.1 and also Dolby for Atmos, which is in 7.1 when played on non-Atmos kit to TrueHD. On my kit the 7.1 is muxed to 5.1.
Could explain some of the differences in sound quality I noticed on the few times I've toggled them in the past.
I always check out the audio setup before playing but tend just to leave the Dolby TrueHD on if given a choice, unless presented with 5.1 lpcm also.
You need to have Dolby TrueHD and any Atmos metadata decoded by the correct amp, not a player. Selecting LPCM from the disc menu will disregard any Dolby data and you will be a base 7.1 maximum soundtrack.

With blu ray discs, I've just pulled out a dozen or so at random, most either have a Dolby TrueHD or a DTS-HD MA as the main soundtrack, you don't seem to get a mix of the two. If you delve into the various soundtracks then apart from the main soundtrack being DTS-HD then you'll often find that the extras come in either a Dolby 2.0 or 5.1.

With an Atmos disc, certainly on 4K, it's either Atmos or DTS:X but not a choice of two. Some older discs that have a DTS:X soundtrack on the main English presentation with have a Dolby Digital foreign language option.

On SD DVDs you often had a choice of Dolby Digital 5.1 or DTS 5.1 along side LPCM options. On the old DVDs I preferred DTS over Dolby. Now in HD it's a lot closer, although those discs that have really good DTS-HD tracks then the upmixing using Neural:X can be exceptional.
 
You need to have Dolby TrueHD and any Atmos metadata decoded by the correct amp, not a player. Selecting LPCM from the disc menu will disregard any Dolby data and you will be a base 7.1 maximum soundtrack.

With blu ray discs, I've just pulled out a dozen or so at random, most either have a Dolby TrueHD or a DTS-HD MA as the main soundtrack, you don't seem to get a mix of the two. If you delve into the various soundtracks then apart from the main soundtrack being DTS-HD then you'll often find that the extras come in either a Dolby 2.0 or 5.1.

With an Atmos disc, certainly on 4K, it's either Atmos or DTS:X but not a choice of two. Some older discs that have a DTS:X soundtrack on the main English presentation with have a Dolby Digital foreign language option.

On SD DVDs you often had a choice of Dolby Digital 5.1 or DTS 5.1 along side LPCM options. On the old DVDs I preferred DTS over Dolby. Now in HD it's a lot closer, although those discs that have really good DTS-HD tracks then the upmixing using Neural:X can be exceptional.
Exactly this. More and more discs have an Atmos mix now, so using anything other than bitstream would be plain stupid.

I've also yet to come across an Blu ray with both Dolby and DTS lossless codecs - it's one or the other, increasingly Atmos/Dolby True HD. Sometimes in the set up menu on the disc there will be an option for 2.0 PCM as well. But why anyone would chose that above a multichannel Atmos mix is beyond me.
 

Steve356

Distinguished Member
I have at least one BR with both DTS-MA and Dolby TrueHD on it. When I tried switching between the two this morning, I really couldn't hear any difference. Also have some that have DTS-MA and LPCM 5.1 on them and again, when I tried them this morning, I couldn't hear any particular differences. They are all music related BRs.
 

gibbsy

Moderator
I'll only use bitstream for any surround sound disc, whether this is film or music. I have quite a few old DVD concerts that have either a Dolby Digital 5.1 or LPCM 2.0. The Dolby is much better than the LPCM simply because the stereo signal goes through the AV amp and in a lot of cases that will have a detrimental effect on the quality of the audio.

It's not such a problem if you have the luxury of a blu ray player that has analogue outputs and those outputs can be placed into a stereo integrated amp.

A good example of this is the Simon and Garfunkel DVD of their Old Friends Reunion concert. Brilliant 5.1 soundtrack, probably the best I have on DVD, best not mention PQ though as it gruesome. The 2.0 LPCM is flat by comparison going through HDMI to an AV amp, so best avoided.

Even HD audio can vary widely. I have two Mumford and Sons blu ray discs. One has an excellent DTS-HD MA 5.1 the other an Atmos soundtrack. The DTS-HD track slays the Atmos and by some margin. I also have a blu ray of the Moody Blues live from the Greek Theatre this has a stellar DTS-HD MA 5.1, delivers everything in bucket loads. The disc also sports an SD DD 5.1 and LPCM 2.0.
 
I'll only use bitstream for any surround sound disc, whether this is film or music. I have quite a few old DVD concerts that have either a Dolby Digital 5.1 or LPCM 2.0. The Dolby is much better than the LPCM simply because the stereo signal goes through the AV amp and in a lot of cases that will have a detrimental effect on the quality of the audio.

It's not such a problem if you have the luxury of a blu ray player that has analogue outputs and those outputs can be placed into a stereo integrated amp.

A good example of this is the Simon and Garfunkel DVD of their Old Friends Reunion concert. Brilliant 5.1 soundtrack, probably the best I have on DVD, best not mention PQ though as it gruesome. The 2.0 LPCM is flat by comparison going through HDMI to an AV amp, so best avoided.

Even HD audio can vary widely. I have two Mumford and Sons blu ray discs. One has an excellent DTS-HD MA 5.1 the other an Atmos soundtrack. The DTS-HD track slays the Atmos and by some margin. I also have a blu ray of the Moody Blues live from the Greek Theatre this has a stellar DTS-HD MA 5.1, delivers everything in bucket loads. The disc also sports an SD DD 5.1 and LPCM 2.0.
Your musical tastes don't get any better I'm afraid Gibbsy. You'll be telling us next that you have a Des O'Connor DVD. :p
 

gibbsy

Moderator
Your musical tastes don't get any better I'm afraid Gibbsy. You'll be telling us next that you have a Des O'Connor DVD. :p
Oh I've got a few James Taylor, Carole King and Super Tramp discs as well and if you delve into my CD collection most go back to the 60s, the golden age of music and some great live concerts. I went to quite a few of them.........so I've been told, can't even remember seeing The Who.
 
Oh I've got a few James Taylor, Carole King and Super Tramp discs as well and if you delve into my CD collection most go back to the 60s, the golden age of music and some great live concerts. I went to quite a few of them.........so I've been told, can't even remember seeing The Who.
The Who are cool, granted. Well they were before they started dying off or going stone deaf.
 

IvanFraser

Member
Exactly this. More and more discs have an Atmos mix now, so using anything other than bitstream would be plain stupid.

I've also yet to come across an Blu ray with both Dolby and DTS lossless codecs - it's one or the other, increasingly Atmos/Dolby True HD. Sometimes in the set up menu on the disc there will be an option for 2.0 PCM as well. But why anyone would chose that above a multichannel Atmos mix is beyond me.
You might get older titles remastered with a selection of audio options, such as original mono or 2ch stereo, further upmixed with quad or 5.1 or 7.1 options too.
I like to play older movies at times in their original mono or stereo through my stereo kit.
Perhaps that choice bewilders you too :0)
I haven't got Atmos, or even 7.1. Atmos to TrueHD is default through my kit with the 7.1 downmixed into the 5.1. So I think the questions exploring a potential benefit for pcm over bistream is valid as an idea.
Or are we all just stupid?
Yes, there are still folks out there using plain 5.1 or stereo (christ, even some of us still watching dvds and wanting them in the correct ratio right across our 16:9 screens - nods to the 9000 thread argument).
I don't know if older gear would have an advantage in outputting lossless codecs to pcm first, but it's a possibility that I haven't been able to nail down as any kind of consensus. Whatever works best is always, er, best.
So, if it is true there's no difference between lossless bitstream and pcm, as is oft claimed, there should be no problem converting to pcm at source, rather than amp, and if the amp does pcm better than bitstream, it would be...best.
That possible setup may be beyond you, I'm sorry about that. But us troglodite luddites (for that read just not paid enough to afford the latest Atmos setup) can occasionally still have outmoded ideas that aren't necessarily negated by the fact that some people have tech that is superior :0) (jealous)
 
You might get older titles remastered with a selection of audio options, such as original mono or 2ch stereo, further upmixed with quad or 5.1 or 7.1 options too.
I like to play older movies at times in their original mono or stereo through my stereo kit.
Perhaps that choice bewilders you too :0)
I haven't got Atmos, or even 7.1. Atmos to TrueHD is default through my kit with the 7.1 downmixed into the 5.1. So I think the questions exploring a potential benefit for pcm over bistream is valid as an idea.
Or are we all just stupid?
Yes, there are still folks out there using plain 5.1 or stereo (christ, even some of us still watching dvds and wanting them in the correct ratio right across our 16:9 screens - nods to the 9000 thread argument).
I don't know if older gear would have an advantage in outputting lossless codecs to pcm first, but it's a possibility that I haven't been able to nail down as any kind of consensus. Whatever works best is always, er, best.
So, if it is true there's no difference between lossless bitstream and pcm, as is oft claimed, there should be no problem converting to pcm at source, rather than amp, and if the amp does pcm better than bitstream, it would be...best.
That possible setup may be beyond you, I'm sorry about that. But us troglodite luddites (for that read just not paid enough to afford the latest Atmos setup) can occasionally still have outmoded ideas that aren't necessarily negated by the fact that some people have tech that is superior :0) (jealous)
No need to get defensive mate. A 5.1.4 Atmos system can be put together relatively cheaply nowadays, certainly nothing elitist about it.
 

Clem_Dye

Distinguished Member
From these posts can I conclude that using LPCM looses Atmos metadata? If so, what’s the real point of it, other than for ‘legacy’ services?
 

IvanFraser

Member
No need to get defensive mate. A 5.1.4 Atmos system can be put together relatively cheaply nowadays, certainly nothing elitist about it.
But who wants 'cheap'?
Anyhoo - how would you know what is affordable to people? A few hundred quid to a lot of people would be a fortune. The difference between eating and not. And I'm not overstating that.
Some people have no perspective on the realities and hardships in society and seem to make a lot of unreasonable assumptions about others based upon their own narrow experience or outlook.
 

IvanFraser

Member
From these posts can I conclude that using LPCM looses Atmos metadata? If so, what’s the real point of it, other than for ‘legacy’ services?
Was that comment serious?
Like, 'what's the point of non-Atmos'?
Atmos is only 5 minutes old. I would suggest that most people don't have the latest spangly tech in their arsenal and, like me, are still on the old 5.1.
And that's kind of my point. To discuss whether or not there may be any benefit for older (not redundant) amps to have a pcm version fed into the amp rather than bitstreamed.
 
From these posts can I conclude that using LPCM looses Atmos metadata? If so, what’s the real point of it, other than for ‘legacy’ services?
You may well ask.........
 
But who wants 'cheap'?
Anyhoo - how would you know what is affordable to people? A few hundred quid to a lot of people would be a fortune. The difference between eating and not. And I'm not overstating that.
Some people have no perspective on the realities and hardships in society and seem to make a lot of unreasonable assumptions about others based upon their own narrow experience or outlook.
You sound like a foodbank volunteer now Ivan. Lighten up mate, it's an expensive hobby, but no one is forced to participate.
 

IvanFraser

Member
You sound like a foodbank volunteer now Ivan. Lighten up mate, it's an expensive hobby, but no one is forced to participate.
On a more serious note. It is expensive.
Some people save up a lot of hard earned dough to buy this kit and can't really afford to move on to newer tech. Which is why things are traditionally backwards compatible.
Personally, the debate is more about fine tuning a system for what is most accurate. If a modern Atmos amp can unpack the native channels perfectly and losslessly, and you have one, you're cooking with gas.
If you have an older non-Atmos 5.1 amp, it's theoretically possible that a conversion in the much newer player, rather than amp-side, would yield a better result.
If you are fortunate enough to have the latest gear, then you probably couldn't 'give a monkeys', which is reasonable.
 

IvanFraser

Member
I have at least one BR with both DTS-MA and Dolby TrueHD on it. When I tried switching between the two this morning, I really couldn't hear any difference. Also have some that have DTS-MA and LPCM 5.1 on them and again, when I tried them this morning, I couldn't hear any particular differences. They are all music related BRs.
The differences are very subtle on my kit.
I think it would take actual objective measurement in situ to nail whether there are any benefits of 1 or the other, in terms of accuracy. So it's all speculation.
Perhaps as an engineer in sound, Steven Wilson's advice to use lpcm rather than DTSHDMA on his discs would indicate that he knows something about its technical merits? Who knows?
 

Clem_Dye

Distinguished Member
Er, I was asking a serious question. This whole support/lack of support for DTS codecs in new kit is troubling. If I'm 'forced' to use LPCM because of a lack of DTS support then presumably, I'm covered for 'legacy' multi-channel audio. But what about Atmos? Am I going to have to play the game of 'guess the codec' and keep altering device settings? I was under the impression that LPCM was a 'one size fits all'. Or not.
 

IvanFraser

Member
Er, I was asking a serious question. This whole support/lack of support for DTS codecs in new kit is troubling. If I'm 'forced' to use LPCM because of a lack of DTS support then presumably, I'm covered for 'legacy' multi-channel audio. But what about Atmos? Am I going to have to play the game of 'guess the codec' and keep altering device settings? I was under the impression that LPCM was a 'one size fits all'. Or not.
I didn't know that they were pulling DTS support on new kit. That's very concerning.
LPCM was put out for early brs for multichannel lossless playback because it was indeed compatible with amps of that era. Many people still not upgraded to lossless Dolby and DTS-capable kit.
But as a lossless format inherently, it still has legs and is featured on some of the latest surround mixes by the likes of Steven Wilson.
It should be around for a long time to come too, as all (most) of the recording kit is based on lpcm.
If a player could unpack the DTS to pcm losslessly in the player, then there would be no concerns about accurate playability up to 7.1 channels.
What it would banjax would be the height-enabled DTS codecs.
I don't understand why they would want to limit kit to exclude such a well-established format as DTS.
 
I didn't know that they were pulling DTS support on new kit. That's very concerning.
LPCM was put out for early brs for multichannel lossless playback because it was indeed compatible with amps of that era. Many people still not upgraded to lossless Dolby and DTS-capable kit.
But as a lossless format inherently, it still has legs and is featured on some of the latest surround mixes by the likes of Steven Wilson.
It should be around for a long time to come too, as all (most) of the recording kit is based on lpcm.
If a player could unpack the DTS to pcm losslessly in the player, then there would be no concerns about accurate playability up to 7.1 channels.
What it would banjax would be the height-enabled DTS codecs.
I don't understand why they would want to limit kit to exclude such a well-established format as DTS.
It's only on (some) TVs - AVRs continue to support it. LG's rationale for discontinuing DTS support is that all the TV based apps such as Netflix. Prime and Disney + all use Dolby - so DTS is not required.
 
I didn't know that they were pulling DTS support on new kit. That's very concerning.
LPCM was put out for early brs for multichannel lossless playback because it was indeed compatible with amps of that era. Many people still not upgraded to lossless Dolby and DTS-capable kit.
But as a lossless format inherently, it still has legs and is featured on some of the latest surround mixes by the likes of Steven Wilson.
It should be around for a long time to come too, as all (most) of the recording kit is based on lpcm.
If a player could unpack the DTS to pcm losslessly in the player, then there would be no concerns about accurate playability up to 7.1 channels.
What it would banjax would be the height-enabled DTS codecs.
I don't understand why they would want to limit kit to exclude such a well-established format as DTS.
It's only on (some) TVs - AVRs continue to support it. LG's rationale for discontinuing DTS support is that all the TV based apps such as Netflix. Prime and Disney + all use Dolby - so DTS is not required.
 

IvanFraser

Member
It's only on (some) TVs - AVRs continue to support it. LG's rationale for discontinuing DTS support is that all the TV based apps such as Netflix. Prime and Disney + all use Dolby - so DTS is not required.
Okay, that's slightly better news.
So what happens if you have dts to tv, such as a networked file or disc? Does the tv pass it on to the amp as 2ch pcm? Coz that's a fairly standard phenomenon anyway.
Surely it wouldn't just end up as silence - tv end?
 

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