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SACD vs. DVD-Audio, High Definition Formats Evaluation
jkml
post Aug 17 2004, 16:24
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A very interesting article at Digit-Life.com:

http://www.digit-life.com/articles2/sacd-dvd-a/index.html
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SebastianG
post Aug 17 2004, 20:25
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Thanks. It was an interesting read. Especially the part about SACDs being currently mastered from a PCM source which makes the DSD (direct stream digital) format not very direct as opposed to the actual idea behind the DSD techonolgy. smile.gif

In the end it's all the same. The conversion for the 1bit DACs from processed PCM material is done for SACDs before mastering and for DVD-As while playback .

Sebastian
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atici
post Aug 17 2004, 20:30
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QUOTE
CD-DA format (PCM 16bit 44100Hz stereo) became obsolete long ago, its limitations do not allow to reach the level, required by today's music lovers. We cannot obviously ignore the incredibly large CD-DA market, which cannot be even approached by SACD and DVD-A. But just few years ago the same thing would apply to the market of video cassettes and DVD-Video discs. Popularity of the CD-DA format and it's ease of use do not allow to predict that this format would end like VHS, but nevertheless, its substantial limitations such as frequent clipping (signal limiting) because of the wish of an audio engineer to achieve a maximum dynamic range, the spectrum limitations (they are discussed in this article below), and new interfaces supporting high definition formats in unfailing digital form to transfer among devices (i-link, HDMI, Denon-link, M-link, etc) make us presume that in the nearest future CD-DA will shift to the mass area, as for example, the mp3 domain, making room in the music lovers' sphere for the formats DVD-A, SACD, and HD-DVD promoted by Microsoft (WMV9 Pro supporting multi-channel audio 24bit 96 kHz WMA9 Pro). The comparison of multi-channel audio and stereo, their pros and cons is an other story


Smells like BS cool.gif


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breez
post Aug 17 2004, 21:03
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Yep, what about using the CD format properly before moving on to 'better' formats rolleyes.gif
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dreamliner77
post Aug 17 2004, 21:11
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QUOTE (atici @ Aug 17 2004, 03:30 PM)
QUOTE
its substantial limitations such as frequent clipping (signal limiting) because of the wish of an audio engineer to achieve a maximum dynamic range


Smells like BS cool.gif
*




WTF....Acheive maximum dynamic range??? They're removing all dynamic range, and regardless, this isn't a shortcoming of the format, just the engineers/masterers.


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LIF
post Aug 17 2004, 22:39
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In my opinion, CDA still very usable and the main reason behind the industry pushing these new solutions, is because they offer better support to copy control and such.
Can you guys imagine in the near future, DVD-A disks having not only copy protection, but region control too(like DVD video), making any album bought overseas not playable at all?

This post has been edited by LIF: Aug 17 2004, 22:39


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M
post Aug 18 2004, 03:50
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QUOTE (LIF @ Aug 17 2004, 04:39 PM)
Can you guys imagine in the near future, DVD-A disks having not only copy protection, but region control too(like DVD video), making any album bought overseas not playable at all?
*

Kind of ironic, when you realize that a number of industry heavyweights' first exposure to the music that ultimately hooked them was imported from some country other than their own....

- M.
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askoff
post Aug 19 2004, 15:37
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I have no intrests of abandon normal CD until there is format what I can copy. I have so many original CD's lost or badly scrached because I had not CD-RW drive those days.
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2Bdecided
post Aug 19 2004, 16:01
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QUOTE
"Although human hearing is generally very poor above 20,000 Hertz, ultrasonic frequency roll-offs produce phase and amplitude effects in the audible region; for example, a single pole (6dB/octave) roll-off at 30  kHz produces about 9 phase lag and 0.5 dB loss at 10  kHz. The effects may be subtle, but their audibility is undesirable in a piece of equipment whose performance is judged by its neutrality."


An analogue, or designed-to-match-analogue digital filter will have phase issues within the pass band - that's certainly true. However...


QUOTE
Thus, being aware of our hearing sensitivity to phase distortions, we can presume considerable decrease in the level of such distortions in the systems with a wider signal spectrum (including the quality LP playback).


Rubbish! For one thing, on a digital system we can cut everything above (say) 20kHz by (say) 140dB while introducing exactly zero phase shift at frequencies below 20kHz. Also, you won't find a phono cartridge with anything like this kind of phase accuracy.


I found much of this article difficult to read. Half the time, it's not entirely clear what the author is trying to say. Though one of the main themes seems to be that many SACDs and DVD-As are mastered from ~20kHz band limited sources - that wouldn't surprise me - most of the normal audio world still uses 24-bit 48kHz.


QUOTE
the entire DSD stream mastering is possible without the PCM conversion, and thus the problem of quality loss in discs disappears.


Rubbish - there are three options:
1. Do everything in analogue except the final DSD encoding
2. Process in DSD wide - this is 8-bit, not 1-bit, hence it's just high sample rate PCM with a lot of ultrasonic noise.
3. Process in DSD - every operation generates a multi-bit signal which had to be dithered/noise-shaped back to 1-bit. This isn't liked because the ultrasonic noise accumulates with every operation.

Cheers,
David.
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danbee
post Aug 19 2004, 16:05
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I'm more than happy with the quality of a well produced and mastered audio CD and see no reason to change.


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CSMR
post Aug 19 2004, 16:20
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QUOTE (breez @ Aug 17 2004, 12:03 PM)
Yep, what about using the CD format properly before moving on to 'better' formats rolleyes.gif

It's the people who are using the CD format properly (not me) who want this new stuff. I consider these future technologies in any case - with the scarcity of releases in these formats. Will they take off before discs are made obsolete as Gates predicts? I don't know.
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pika2000
post Aug 19 2004, 17:19
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I agree with LIF. I won't be buying the new formats. I want my music media to be flexible. I cannot backup SACD/DVD-A. Also, I want to listen my music where/whenever I want to, not stuck in front of a home theater system. Copy protection is what interests the recording companies, not sound quality. Do you guys remember pre-recorded MDs?


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krabapple
post Aug 19 2004, 18:32
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NB that the author of the webpage runs a component modification business; which gives hima potential stake in potentially pointless tweaks; he does however post regularly and informatively on AVSforum.com forums (under the moniker 'Gordon MacGregor' for some reason).
I suspect the article was translated from Russian, hence the slight obscurity of some of the language.

Seems to me he glided too glibly over the actual audibility of all this >20 kHz information, which is a foundational issue for the rest of his claims.

I buy SACDs and DVDas to 1) hear a different mastering, often *claimed* to have been from better sources/done more carefully and 2) for multichannel mixes. I don't put much stock in claims that the playback higher resolution or bitdepth makes much difference.

This post has been edited by krabapple: Aug 19 2004, 18:37
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krabapple
post Aug 19 2004, 18:42
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QUOTE (SebastianG @ Aug 17 2004, 11:25 AM)
Thanks. It was an interesting read. Especially the part about SACDs being currently mastered from a PCM source which makes the DSD (direct stream digital) format not very direct as opposed to the actual idea behind the DSD techonolgy. smile.gif

In the end it's all the same. The conversion for the 1bit DACs from processed PCM material is done for SACDs before mastering and for DVD-As while playback .

Sebastian
*



You might be interested to know that the engineers at Deutsche Grammaphon, the big classical label, considered both PCM and DSD for their digital archiving, and decided to go with PCM, based (they say)
on their comparative technical merits. So all their SACDs are sourced from 'hi rez' PCM transfers/remixes of their original master tapes.
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Alex Striganov
post Aug 19 2004, 20:15
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Hello everybody!
QUOTE (krabapple @ Aug 19 2004, 09:32 AM)
NB that the author of the webpage runs a component modification business; which gives hima potential stake in potentially pointless tweaks

Interesting how my business is related to the article and why everyone wants to discuss it? It is not pointless if you will visit DIYAUDIO forum and ask people if there is any difference in op amps sounding ...
QUOTE
he does however post regularly and informatively on AVSforum.com forums (under the moniker 'Gordon MacGregor' for some reason).[/b]

Yes, I do, and I used the same pseudonym Gordon McGregor in all forums around the world. The reason is - I used it online till 7 years ... starting from Ultima Online, as I had no idea to publish articles and confuse people ... smile.gif
My friend is from Clan McGregor ...
QUOTE
I suspect the article was translated from Russian, hence the slight obscurity of some of the language.

You hit the nail on the head! Digit-life is owned by the best Russian hardware website - iXBT.com and they have translated my article, published in Russian three weeks ago. I don't like the translation and intend to make my own.
QUOTE
Seems to me he glided too glibly over the actual audibility of all this >20 kHz information, which is a foundational issue for the rest of his claims.

OK, here is the scientific confirmation, that we can recognize hypersonic images, not separated from the audible signal:
http://jn.physiology.org/cgi/content/abstract/83/6/3548 Full article is in pdf file at this link.
QUOTE
I buy SACDs and DVDas to 1) hear a different mastering, often *claimed* to have been from better sources/done more carefully and 2) for multichannel mixes.  I don't put much stock in claims that the playback higher resolution or bitdepth makes much difference.

it really depends on the equipment used. From analog output of 47Ai I also don't hear a huge difference between the Hi-Res formats and CDs ... completely different story in multi-channel mode through i-link ...

Concerning CDs. We definitely don't have phase shift using FIR Brickwall, but I was talking in the article about analog anti-aliasing filters. I also stated clearly, that correctly mastered and played CDs can sound better, then non-correctly played Hi-Res formats. For example - CDs, created using perfect dithering algorithms as ExtraBit, A/D conversion at the high sampling rate and resolution, processing in the good professional software using FIR cut-off, etc. can sound very good, using the good CD player.
I had auditioned such systems - for example CD in dCS CD->DSD upsampling mode was sounding almost perfectly ... http://members.cox.net/alex_lat/images/dCS.jpg
But we have to take in mind that there are not so many perfectly mastered CDs available, even in our days some modern CDs are badly clipped - take a look at Diana Krall 2001 album, even the first song has 25 possibly clipped samples in one channel and 110 in another one ... How can we find out which one is good and which one is not good? Check them all? I prefer to use High-Res formats, they have no such problem and sound significantly better anyway ... http://members.cox.net/alex_lat/Tests/Statistics_DK.JPG it had been ripped by EAC to HDD ... here is the zoomed version:
http://members.cox.net/alex_lat/Tests/DK_CD_clipped.PNG
I am open to discussions and have nothing against being corrected by the knowledgeable people ... we all are studying ...

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krabapple
post Aug 19 2004, 20:36
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QUOTE
Interesting how my business is related to the article and why everyone wants to discuss it? It is not pointless if you will visit DIYAUDIO forum and ask people if there is any difference in op amps sounding.


I may do that, but I can tell you in advance that anecdotal , sighted reports of difference from 'satisfied customers' hold no weight with me -- confirmation bias is simply too strong a possibility.
(And note that I wrote 'potential' both times ;>)

QUOTE
QUOTE
he does however post regularly and informatively on AVSforum.com forums (under the moniker 'Gordon MacGregor' for some reason).[/b]

Yes, I do, and I used the same pseudonym Gordon McGregor in all forums around the world. The reason is - I use in online, as I had no idea to publish articles and confuse people ... smile.gif


I still like my 'superhero' theory, though. ;>

QUOTE
QUOTE
Seems to me he glided too glibly over the actual audibility of all this >20 kHz information, which is a foundational issue for the rest of his claims.

OK, here is the scientific confirmation, that we can recognize hypersonic images, not separated from the audible signal:
http://jn.physiology.org/cgi/content/abstract/83/6/3548 Full article is in pdf file at this link.


And you should look up the discussions of Oohashi's work, here, and on other audio forums. For starters, it's work that used 'home made' equipment, hasn't ever been replicated, and has some *counterevidence* from other research, going against it. Nor does it really show that people *hear* ultrasonics.

QUOTE
QUOTE
I buy SACDs and DVDas to 1) hear a different mastering, often *claimed* to have been from better sources/done more carefully and 2) for multichannel mixes.  I don't put much stock in claims that the playback higher resolution or bitdepth makes much difference.


it really depends on the equipment used. From analog output of 47Ai I also don't hear a huge difference between the Hi-Res formats and CDs ... completely different story in multi-channel mode through i-link ..

Concerning CDs. We definitely don't have phase shift using FIR Brickwall, but I was talking in the article about analog anti-aliasing filters. I also stated clearly, that correctly mastered and played CDs can sound better, then non-correctly played Hi-Res formats.


Which only restates that *implementation matters*. The more fundamental question, though, is whether the formats are intrinsically different-sounding. If not then it's *all* about implementation, and there really is no need for SACD or DVD-A *playback*, except for multichannel. There is only a need for *properly done* CD.

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Garf
post Aug 19 2004, 20:46
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QUOTE (Alex Striganov @ Aug 19 2004, 09:15 PM)
But we have to take in mind that there are not so many perfectly mastered CDs available, even in our days some modern CDs are badly clipped - take a look at Diana Krall 2001 album, even the first song has 25 possibly clipped samples in one channel and 110 in another one ... How can we find out which one is good and which one is not good? Check them all? I prefer to use High-Res formats, they have no such problem and sound significantly better anyway ...


The "high-res formats" are definetely susceptible to clipping, just like CD Audio is. If the behaviour of the recording industry in the past is any indicator then we will get badly clipped DVDA/SACD as soon as the formats are a bit more whidespread. It's all about being the loudest, "sound quality" is just something to lure early adopters with.
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Garf
post Aug 19 2004, 20:50
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QUOTE (Alex Striganov @ Aug 19 2004, 09:15 PM)
OK, here is the scientific confirmation, that we can recognize hypersonic images, not separated from the audible signal:
http://jn.physiology.org/cgi/content/abstract/83/6/3548 Full article is in pdf file at this link.


As far as I know this study is still considered highly controversial. I don't think you can convincingly push it as "scientific confirmation" until the results are confirmed by other research.
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Alex Striganov
post Aug 19 2004, 21:04
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Guys I really don't like this forum services. I wrote the reply, being logged in, tried to send it, it says "you don't have the permisson" (it means it logged me out after some time?) and then the post disapeared ... Need to re-write everything again and it is at least 30 min ... grrr
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bryant
post Aug 19 2004, 21:38
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QUOTE (Alex Striganov @ Aug 19 2004, 12:04 PM)
Guys I really don't like this forum services. I wrote the reply, being logged in, tried to send it, it says "you don't have the permisson" (it means it logged me out after some time?) and then the post disapeared ... Need to re-write everything again and it is at least 30 min ... grrr
*

I've been burned by that too! sad.gif I now write every post longer than one paragraph in WordPad and copy+paste it in.
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WmAx
post Aug 19 2004, 23:14
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QUOTE
OK, here is the scientific confirmation, that we can recognize hypersonic images, not separated from the audible signal:
http://jn.physiology.org/cgi/content/abstract/83/6/3548 Full article is in pdf file at this link.


1st - this test did not confirm adubility -- the 'audibility' portion of this test has not much information published and is questionably valid 2nd - this test focused primarily on brain scan activity 3rd - the test could not produce any result of any type when only ultrasonic information was presented. -- only when both ultrasonic and sonic data was presented. 4th - NHK labs to to task this study, and produced a careful perceptual test:

Perceptual Discrimination between Musical Sounds with and without Very High Frequency Components
Toshiyuki Nishiguchi, Kimio Hamasaki, Masakazu Iwaki, and Akio Ando
AES Preprint: 5876

Since probably don't want to dish out $$ for the paper, it is lucky this is one of the few AES papers availabe online for free, since it was also published on the NHK webstie:

http://www.nhk.or.jp/strl/publica/labnote/lab486.html

QUOTE
Concerning CDs. We definitely don't have phase shift using FIR Brickwall, but I was talking in the article about analog anti-aliasing filters.


Their is no evidence that properly contstructed anti-alias filter, even analogue, will have audible consequences. Refer to the landmark perceptual paper, that used such steep filters:

What Bandwidth Is Nescarry For Optimal Sound Transmision
Plenge, Jakubowski and Schone
JAES, 1980, Volume 26, Number 3, Pages 114-119

I would also refer you to a later paper on the audibility of anti-alias filters:

Perception of Phase In Anti-Alias Filters

Pries and Bloom
AES Preprint: 2008

-Chris

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Alex Striganov
post Aug 19 2004, 23:20
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Thank you for your inputs, guys!
QUOTE (krabapple @ Aug 19 2004, 11:36 AM)
I may do that, but I can tell you in advance that anecdotal , sighted reports of difference from 'satisfied customers' hold no weight with me -- confirmation bias is simply too strong a possibility.
(And note that I wrote 'potential' both times ;>)

We have a lot of opinions of well known respected people in audio, for example Doug Self's ... and many others, the whole tweaking industry is based on this principle. "Potentially" is a nice word, potentially I hate you ... what does it mean? Please note that I have no reason to hate you in reality nor any intention to abuse you, just used your word smile.gif
I tried to make a suggestion about the difference, it is here - has to replace the old measurements with my Audigy with the new ones through Lynx L22 though.
http://members.cox.net/alexhardware/opa.htm
In the DBT I can recognize the difference between PCM1704+OPA627+OPA2134 and PCM1704+JRC5534+JRC2068+JRC2068 with 17/19 probability in the best case, usually it is 14-15/19 ... You still don't think it is enough information to make the suggestion? Well, this is a point to write another article, it is "on the way" smile.gif
QUOTE
I still like my 'superhero' theory, though. ;>

I don't think that I am any kind of "superhero", though potentially you know better wink.gif
QUOTE
And you should look up the discussions of Oohashi's work, here, and on other audio forums.   For starters, it's work that used 'home made' equipment, hasn't ever been replicated, and has some *counterevidence* from other research, going against it.  Nor does it really show that people *hear* ultrasonics.

I know that anything can be blamed - bad equipment, bad sources of information, etc., etc. Please supply those opposite sources, we can discuss them as well. I am not a scientist, but I hear the difference using DBT as stated in the article, with 19/19 probability, and it looks as the samples are different only in the ultrasonic area ... I also see the ultrasonic images, and I have no other idea how to explain the difference in sounding through the same path ... there is no difference in implementation, as for PCM exactly the same path is used.
QUOTE
Which only restates that *implementation matters*. The more fundamental question, though, is whether the formats are intrinsically different-sounding.   If not  then it's *all* about implementation, and there really is no need for SACD or DVD-A *playback*, except for multichannel.  There is only a need for *properly done* CD.

In the same best conditions High-Res format is a winner (I am talking about presented in the article DVD-A Advanced resolution and SACD multi-channel), in other case they are simply useless (and we know that this is not true). I can hear the difference through my system easily - as stated before, the same path for PCM audio signals. Not only me - as the moderator of this forum pio2001 said, and I agree with him:
QUOTE
However, ABX success seem to show that after all, there might be an audible difference between a 44.1/16 bits recording and a 96/24 bits one, whatever causes this.

To confirm this statement I am going to make an experiment - using Adobe Audition 1.5, record the sample of High-Res audio signal in 24/96 mode, then convert it to 16/44.1 using two algorithms of resampling - SSRC or PPHS plus different kinds of dithering, including ExtraBit and compare the results through DBT. The files will be provided for downloading. I don't have any other idea how to prove it, may be you can recommend something? I know about this website http://64.41.69.21/technical/sample_rates/index.htm , but they did't use ExtraBit and different re-samplers AFAIK, though their samples could be useful for expariments.
Concerning IMD, I use M&K S-150 speakers, which were designed with lowering of IMD in mind, as stated at M&K website, using two tone (means standard) IMD measurements. My measurements of 49TXi audio signal path including A/D stage of Lynx L22 path also shows quite low level of IMD:
IMD, %: 0.0073 Excellent
I can't be 100% sure, but can make some suggestion that the level of IMD in my DBT is quite low. It is not a scientifical provement though, I need AP and a great mic to confirm that. Please note, that the article is not scientific, if you have any scientific information to show me where I was wrong, I will be glad to correct it.
QUOTE (Garf @ Aug 19 2004, 11:46 AM)
The "high-res formats" are definetely susceptible to clipping, just like CD Audio is. If the behaviour of the recording industry in the past is any indicator then we will get badly clipped DVDA/SACD as soon as the formats are a bit more whidespread. It's all about being the loudest, "sound quality" is just something to lure early adopters with.

I never met even 1 SACD or DVD-A with clipping. I will gladly buy the disk with such problem, if you can recommend me any. As as we can see, 2001 CD is not relative to "early adopters" ...
QUOTE
As far as I know this study is still considered highly controversial. I don't think you can convincingly push it as "scientific confirmation" until the results are confirmed by other research.

First of all Nelson Pass's statement in the article is based on Ph.D. Steven Dear researches in the same area, so we have some "other researches".
Highly controversial? It is published in the well-respected Journal of Neuropsychology, 10 people are co-authors in it, it is "scientifical enough" for me. Can you provide the links with the opposite information? If you are talking about this document http://www.nhk.or.jp/strl/publica/labnote/lab486.html I have some points to discuss. I did DBT and easily recognized that it is necessary to know what difference are you going to hear and train yourself for a while, then it becomes completely different. If you use just some participants who know nothing about the test, the probability that they can hear the difference is very low when signals are more or less equal. A very important point, which never had been discussed or researched - ultrasonic images in multi-channel audio, we have a significant difference in perception of it vs stereo or even mono signals, usually used in the tests.

This post has been edited by Alex Striganov: Aug 19 2004, 23:40
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lexor
post Aug 19 2004, 23:40
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The article also states:
QUOTE
and HD-DVD promoted by Microsoft (WMV9 Pro supporting multi-channel audio 24bit 96 kHz WMA9 Pro)


That is incorrect/misleading! Though Microsoft does provide such capabilities in their WMEncoder, such audio is NOT part of HD-DVD specification ratifiend by the DVD forum and will not be found on future HD-DVD disks.

Dolby, DTS, LPAC (lossless), and mp4 (including HE and that new stuff Nero is working on to improve it, I'm bad with acronims) are the codecs. Only WMV9 Video has been approved.

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Alex Striganov
post Aug 19 2004, 23:45
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QUOTE (WmAx @ Aug 19 2004, 02:14 PM)
the test could not produce any result of any type when only ultrasonic information was presented. -- only when both ultrasonic and sonic data was presented.

This is a very important point as well. Dr. Griesinger's presentation shows us that we definitely can't hear the separated ultra-sonic images - he had a perfect experiment with the keys.
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WmAx
post Aug 19 2004, 23:48
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QUOTE
I am not a scientist, but I hear the difference using DBT as stated in the article, with 19/19 probability, and it looks as the samples are different only in the ultrasonic area


Of course, a valid DBT that can be accepted as credible requires some signficant effort and resources. Just review any of the peer-reviewed/scrutinized studies, to see the general level of effort and statistics required for a meaningful DBT. The ABX tests produced by this site are useful for thie purposes, but do to lack of actual controls(remote testing - no verification, etc.) and procedure, would not hold up under hard scrutiny -- though far more useful then a standard sighted subjective test.

Do you realize the 'audibility' chart on your site pertains to pure sinuisodal waveforms? The tolerances for audbility are far higher with music program. Even, with a purist piano recording, the JNDs are in the 1-2% average range of total THD of detectiablity thresholds for listeners:

Just Detectable Distortion Differences
Wireless World, February, 1981, pages 32, 33, 34 and 38
James Moir

-Chris
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RSS Lo-Fi Version Time is now: 17th September 2014 - 20:54