Why is Blu-ray audio better than standard DVD audio?

[bigburner]

People rave about the audio quality on Blu-ray DVDs. Why?

A standard DVD includes an LPCM uncompressed 2-channel mix sampled at 48 or 96kHz with 16 or 24 bits/sample.

A Blu-ray DVD includes a Dolby TrueHD 5.1 surround mix sampled at 48kHz with 24 bits/sample and an LPCM uncompressed 5.1 surround mix sampled at 48kHz with 16 bits/sample (I think!).

OK, ignoring the fact that one is 2-channel and the other is 5.1, why is the quality of Blu-ray audio supposed to be a lot better than standard DVD audio? In some cases standard DVD should be better, eg 96kHz with 24 bits/sample.

What have I missed here?

Nigel.

[Jack Gilvey]

The whole point of the new codecs is the ability to deliver 7.1 lossless channels. If all you want is stereo, then these codecs offer little over DVD from a technical standpoint. I'd rather have a good DD+/DTS Core 5.1 for movies over lossless stereo, myself, still better spatially.

In some cases standard DVD should be better, eg 96kHz with 24 bits/sample.

Depends on the master. For the most part, BD delivers what was on the encoding master. Some raw LPCM tracks are apparently downsampled, but TrueHD/DTS MA tracks need not be.

[wettou]

Just try it and then you will see, or should I say hear

[bigburner]

Just try it and then you will see, or should I say hear

That may be true but there must be a good reason. That's why I started the thread.

[ShadowZA]

Music:

For me, the starting point in the pursuit of critical listening enjoyment is the quality of the recording. I prefer stereo. Hearing artist in front of me. I don't care what the playback codec is. If the recording is not up to scratch, then the deal is off even before first base is reached.

Of course, what I'd like to be able to have most of all, are excellent quality recordings that see their way through to excellent quality & lossless playback methodologies.

Would it be cynical to assume that I'm not too hopeful in having my needs met through any other audio medium at this time other than redbook CD? You decide.

Suffice to say that the humble CD contributes well over 80% to my total audio enjoyment.

Movies:

I prefer multichannel sound due to it providing increased involvement. In addition, it is deemed to be a more complete, detailed and tru-to-life experience if such multichannel sound is lossless. A bit of compression is not a problem, as this simply enables the "lossless" information to be transported speedily through existing bandwidth. As I understand it, the concept of "lossless" induces the feel that all frequencies as per the original recording will be there as is not the case with lossy codecs, even if such lossy information is uncompressed. To put it another way, with lossless codecs you get the Full Monty, a replica of the master recording. Enter the new Dolby True HD & DTS Master Audio lossless codecs found on Blu-ray.

This is how I "think" it is. Hope this helps.

[hifiguymi]

People rave about the audio quality on Blu-ray DVDs. Why?

A standard DVD includes an LPCM uncompressed 2-channel mix sampled at 48 or 96kHz with 16 or 24 bits/sample.

A Blu-ray DVD includes a Dolby TrueHD 5.1 surround mix sampled at 48kHz with 24 bits/sample and an LPCM uncompressed 5.1 surround mix sampled at 48kHz with 16 bits/sample (I think!).

OK, ignoring the fact that one is 2-channel and the other is 5.1, why is the quality of Blu-ray audio supposed to be a lot better than standard DVD audio? In some cases standard DVD should be better, eg 96kHz with 24 bits/sample.

What have I missed here?

Nigel.

What people are commonly referring to when they say BD sounds better is for movies. It's true that you can get a two channel PCM up to a bit depth of 24 bits and a sampling rate up to 96kHz on DVD-Video disc. When you do that it takes up a great deal of space on a disc and you wouldn't be able to have a movie on it as well. For a DVD-Audio disc you can get that for 5.1 channels because of MLP (Meridian Lossless Packing). DVD-A will do up to 24/192 in two channel. Video is very limited on DVD-A discs with that kind of audio resolution.

With BD discs, you can have full high definition video and 7.1 channels of PCM up to 24/96 (it can be anywhere from 16 bit to 24 bit and 48kHz to 96kHz). That is the difference. (I know BD will do up to 192kHz but I'm not sure if it will do it with more than two channels. I can't find the info anywhere. Does any one else know?) There is an audio spec only for BD that is akin to DVD-A but I don't know of any players or discs that focus on it. It's called Profile 3.0. Who knows if we will ever see that appear. The average customer doesn't know, or doesn't care, about DVD-A or SACD much less BD Profile 3.0.

With Dolby TrueHD and dtsHD Master Audio you get the same sound quality (theoretically) that you would with an equivalent PCM track they just save space so movie studios can put more features on a disc.

I hope this helps.

Eric

[ShadowZA]

Found some more info here:

http://www.blu-ray.com/faq/

[littlesaint]

Just a note that film soundtracks are typically only 48/24. Older films are 48/16. Anything more for film is superfluous. There are some video releases, especially concerts, that are multichannel 24/96.

[bigburner]

Would it be cynical to assume that I'm not too hopeful in having my needs met through any other audio medium at this time other than redbook CD? You decide.

Suffice to say that the humble CD contributes well over 80% to my total audio enjoyment.

I can hear the difference between a good 2-channel DVD track and a good CD track, even on my modest system. The DVD track is superior.

The reason for this (I presume) is that the Redbook Standard mandates a sampling rate of 44.1kHz with 16 bits/sample. These are maxima that cannot be exceeded.

In contrast there's much more freedom with the DVD standard which allows a sampling rate of up to 96kHz with a maximum of up to 24 bits/sample.

What I'm trying to work out is whether Blu-ray audio is a further step up in sound quality from DVD.

So far extensive use of Google has not revealed the answer. My Googling has included the http://www.blu-ray.com/faq/ site that you mentioned. In fact it's the first hit using Google.

This forum has many experts and I was rather hoping that one of them would step forward with an informed science-based answer.

For those of us who are primarily into music (rather than movies) this is an important piece of information when deciding whether it's worth spending money on Blu-ray.

Nigel.

[Jack Gilvey]

In contrast there's much more freedom with the DVD standard which allows a sampling rate of up to 96kHz with a maximum of up to 24 bits/sample.

For stereo. BD can match that, and expand it to 8 channels. As I explained, that's the point of the new codecs...multichannel.

This forum has many experts and I was rather hoping that one of them would step forward with an informed science-based answer.

What else are you looking for? I can't see upgrading to BD just for stereo music. And even it can support 192kHz sampling for stereo...so? What's there to listen to, anyway?

[ShadowZA]

What I'm trying to work out is whether Blu-ray audio is a further step up in sound quality from DVD.

I'd like to put my answer forward and say: "Yes, Blu-ray audio definitely has the capacity to offer better sound quality."

The problem I have (and this is the cynical part) is that I'm doubtful that it will be harnessed to its full capacity, mostly, in bringing the best quality out there to its listeners. By best quality I mean sufficient enough, utilizing:

1. The lossless codecs
2. The best recording setups, mics & studio hardware

such that the true audiophile is catered for

Yes, it may sound marginally better than std defn DVD ... but my feel is that even std defn DVD recordings mostly could sound a whole lot better than they do utilizing their existing lossy codecs.

I hope that I am wrong and that recording studios bump up their own hardware & deliver some audiophile grade music on Blu-ray.

[ShadowZA]

I'd like to add further comments in support (hopefully) of what you are asking, Bigburner.

The Blu-ray disc has a much bigger storage capacity than the std defn DVD. This can thus be better utilised in quality delivery of video & audio media.

I think that std defn DVD was mainly intended to replace analogue VHS tape and thus video media was concentrated on. Audiophile quality audio was left to the redbook CD, DVD audio & SACD. Out of these audio delivery formats the CD still remains king. In support of this, please allow a little presumptuousness on my part in declaring that I am still blown over as to how qualitatively amazing a well recorded redbook CD can sound (being played on a reference quality upsampling source) when compared to "good" quality std defn DVD's out there. Being mainly into audio, I sometimes do wish that it was different. Imagine a well recorded audiophile DVD (not DVD audio) being played on a reference quality "upsampling DVD" source just as is the case is and in place of the redbook CD. Doesn't exist ... but you gather what I'm trying to say here.

I understand that us audiophiles are the "little guys" ... but that doesn't stop us wanting the studios to give us the best audio scientifically possible.

[littlesaint]

If anyone wants a good example of Blu-ray's potential for music, Neil Young and Sun Microsystems are teaming up to put his "Archives" release on Blu-ray with BD-Live content.

http://www.msnbc.msn.com/id/24487949/

[ShadowZA]

If anyone wants a good example of Blu-ray's potential for music, Neil Young and Sun Microsystems are teaming up to put his "Archives" release on Blu-ray with BD-Live content.

http://www.msnbc.msn.com/id/24487949/

This is good news indeed. :T

[georgev]

Is it really better? Is there an objectiove way to measure it? I doubt it.
"The proof of the pudding.........." Try a blind test.
Same environment, same equipment(except the players), and listen for any differences. That might be quite telling.
My 0.02cents worth.
George.

[littlesaint]

Is it really better? Is there an objectiove way to measure it? I doubt it.
"The proof of the pudding.........." Try a blind test.
Same environment, same equipment(except the players), and listen for any differences. That might be quite telling.
My 0.02cents worth.
George.

It has the potential to be better. That's all that can be said. The technology is superior. How studios and engineers use the technology determines its ultimate value. CD can be superior to analog recordings when used to its full potential. Unfortunately, these days that is very rare.

[ShadowZA]

... this is an important piece of information when deciding whether it's worth spending money on Blu-ray.

Nigel.

Nigel, let me tell you what I plan to do. Maybe this could assist. As hard as it is NOT to go out there and get a Blu-ray player ... I have decided to wait a bit longer. I'd like to analyse/look around/think about the Blu-ray discs that are about. If, by some miracle, my favourite artists start recording their new stuff, in studio, on BD using latest lossless codecs AND such recordings are quite better than redbook CD ... then I'd prefer to look around for a high-end Blu-ray player. If, as with DVD-video, the picture quality is excellent & movie sound quality is reasonable to excellent BUT my music audiophile passion (obsession?) comes a distant second ... then a reasonable quality Blu-ray player should suit me just fine.

Hey man ... these are the sort of decisions that keep me awake at night. Not easy.

[bigburner]

Good answers thank you chaps.

I get the feeling that if I want to get the best out of Blu-ray I will need to upgrade my equipment to 5.1.

Nigel.