High-Def FAQ: Uncompressed vs. Lossless Audio

Why didn't someone make him say how good DD+ is!!:mad: lol
How about this:
AVS Forum - View Single Post - R&B Films - DRS Mastering for Superior PQ / AQ
I have done level matched side by side's with DD+ 1.5 decodes of "Serenity" and "We Were Soldiers" against the PCM masters...
I couldn't tell the difference, and I mixed "We Were Soldiers."
I mix films for theatrical distribution.... they do indeed have certain unique elements of craftsmanship and technical specifications.
And I don't disagree that most engineers that you speak with agreed with your assessment.
I did too, until I heard DD+ at 1.5.
Please note, this is said by the person that mixed the soundtrack "We Were Soldiers". Is this good enough for you?

Or would you like now somebody say PCM is not better than MP3...? :)

Diogen.
 
Well all that read and in the end the answer is:
The end result is the same whether the disc you buy has an uncompressed soundtrack or a lossless one
 
iCewOlf it sounds like your accepting that all the previous Blu-ray audio talking points are null and void???
 
Just as a side not.
The article linked in the original post was triggered by a (sometimes heated) exchange
between RBFilms (creator ofNature's Journey) and others in multiple threads on AVS.

RBFilms' position on audio has been summarized by Amir in this post
AVS Forum - View Single Post - R&B Films - DRS Mastering for Superior PQ / AQ
Oh, I have an open mind. Believe me. I consider myself a crazy audiophile and have a ton of friends who are the same. I believe in all kinds of esoteric concepts. I can hear fidelity improvements in power cables and interconnects. I can hear the difference between different S/PDIF cables. I can believe how someone thinks their music player system sound worse if a washing machine is running in another room. I can believe how someone thinks that an amp needs to break in for a few hours to sound good. Or how a $20,000 mono amplifier may sound better than a $1,000 one.

Indeed, there are few esoteric theories put out there by audiophiles which both the engineer and audiophile in me doesn't think there may be a shred of truth about it. This didn’t come without having an open mind as you wonder. So none of this is at issue here.

What is at issue is that Rich is making claims I have not heard of anywhere after 30+ years in this business. I have read Perfect Sound for better part of a decade, and even that bible of audiophile music hasn't claimed that MLP codec (i.e. TrueHD) is not really lossless. Or that the same bitstream, coming from first layer of a DVD audio disc sounds different than the second layer. Or that if said stream is being transmitted to an AVR over a link, it can be subject to jitter. The equipment reviews in Absolute Sound read like wine reviews, but even they avoid going where folks seem to have gone here.

Diogen.
 
Here's a concept many of you "kids" were never taught- You kids who grew up in the digital age.
All audio is analog, not digital. Any sound stored as digital has to be a sampling of the analog audio waveform. Therefore by definition, the sound is lossy, by the fact of how the analog waveform is parsed or sampled into 1's and 0's for digital storage and transmission.

What is the first thing we do with sound- We capture the sound as an analog pressure wave into a variable waveform of voltage changes over time. Then it is converted to a digital file structure using analog to digital conversion (Lossy) after it arrives to our home theaters we must convert that digital file back to analog for driving a speaker that does what? It moves the air in our home theaters to a similar pressure wave that was in the original. (Lossy).

The problem technology has always had with analog processing and storage is that the system in analog cannot exclude the noise in the system from contaminating the analog waveform. This is the primary advantage of digital. We sacrifice accuracy in the waveform for a way to eliminate noise contamination. Digital is always lossy but noiseless. It can be achieved with less loss if we integrate the analog waveform finer and finer to a higher sampling. A second problem analog has is it is a non-linear process of amplification and technology never was able to get a perfect reproduction of the original due to this non-linearity. Some believe that the best analog amps are worse than the worst digital processors. However, the theory of analog all the way through should be the most accurate if the technology could make a system that is noise free and truly linear. The best linearity is with class A amplification but as you improve linearity in class A the efficiency drops off rapidly.

I thought the article was very good but only if you are considering sound in the case of these digital systems. I don't agree that the process of digital in audio is ever lossless. It can only be said to be lossless inside the digital box. The losses occur during the conversion from sound we hear to a file in digital and again from that file to a sound we hear.
 
Once again, folks do not read the posts. Excerpts from the above link:

Let's begin by looking at how uncompressed audio works. A PCM track is an uncompressed digital format that is 100% bit-for-bit identical to the studio master.

On the other hand, Dolby TrueHD and DTS-HD Master Audio are "lossless" compression formats. Although they're compressed to take up less disc space than a PCM track, once decoded they're also bit-for-bit identical to the studio master.

Standard Dolby Digital, DTS, and (to a lesser extent) Dolby Digital Plus and DTS-HD High Resolution are all "lossy" compression formats. In the above scenario, they'd not only drop the 0s, but also drop some of the 1s that are deemed less critical to human hearing, under the belief that most people won't be able to hear the difference. The higher the bit rate, the less data is dropped. DD+ and DTS-HD HR are not only higher bit rate than old DD and DTS, but also more efficient at maintaining more of the data at lower bit rates. Still, they're not a perfect replication of the studio master the way that the PCM or TrueHD and Master Audio formats are.

PCM is not needed unless you don't want to decode within the player and have the space and bandwith to push the uncompressed sound track which BD has plenty of both. While HD-DVD uses DD+ primarily and this is better then either DD or DTS it still is not an exact replica of the movie sound track. As for which format uses what, it is the soundtrack and how well it is done that will provide the end results that you would enjoy.

If it does not bother HD-DVD folks to not have the best audio possible why should it bother any BluRay supporter? I don't care if HD-DVD doesn't have the ablility to support a lossless audio track (for whatever reason)-- I support the format that is capable and does support multiple lossless audio tracks on one disc -- BluRay.
 
I don't care if HD-DVD doesn't have the ablility to support a lossless audio track (for whatever reason)-- I support the format that is capable and does support multiple lossless audio tracks on one disc -- BluRay.

Complete you know what. HD DVD supports lossless just fine. As promised earlier in the year, Universal is now using True HD on their releases. Even Paramount has finally gotten into the swing of things. They will be releasing more and more.

The only reason BD needs more bandwidth is because it was originally slated to support MPEG2 for video and PCM for audio. DEcoding of TrueHD and DTS Master is optional in the BD standard. Hence the reason so few players, besides the PS3, support TrueHD and the need for a second lossless PCM track.

S~
 
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I tend to side with the experts, all their well trained ears say that DD+ 1.5 is award winning. Lets say for arguement sake that Blu-ray audio is better on paper(certain movies) but doesn't translate in the real world, it means nothing.
 
I thought the article was very good but only if you are considering sound in the case of these digital systems.
I think he's talking about digital audio only.
It can only be said to be lossless inside the digital box.
Correct. Only within those constraints you can actually talk about "lossless", i.e. it can be proven the compressed track is identical to the uncompressed.
The losses occur during the conversion from sound we hear to a file in digital and again from that file to a sound we hear.
There are people that would not agree with you:
AVS Forum - View Single Post - R&B Films - DRS Mastering for Superior PQ / AQ
Talking about the math, I still remember the day my professor showed the math on the whiteboard. Even after seeing it in black and white, I still couldnt' believe those "stair-step" pulses could be shown to be the same as the analog waveform. But there it was. It is one of those most non-intuitive things in A/V world. Even codec algorithms are much simpler to explain than this one.

Diogen.
 
Reviving this old high resolution audio thread:
One of the most celebrated dual format HD/BD release - Nature's Journey done by R&BFilms -
had different audio tracks: lossy DTS in HD and lossless on BD (from a 96kHz master).

Using a professional Audio Precision Analyzer, the Onkyo 805 AVR and comparing the HD/BD
versions of Nature's Journey, there seem to be no traces of any sound above 48kHz.
Advanced topics in HD audio - Page 5 - AVS Forum
Interesting read.

Diogen.
 
Great write up Don...

As far as the stair step stuff pointed out by Diogen, Don is right. Its still a loss. The detail comes with the sampling rate. The higher the sampling rate, the more you reduce the size of the width of the individual sample pulses. Of course you also need more bits to also handle the quantization issues. You'll never get the exact representation of the old analog waveform, but the goal is to produce a wave form close enough that the ear cannot perceive the difference.
 

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