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  • dekkersj
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Is DVD Audio necessary ?
Reply #25
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This is true to an extent, but considering that Philips are very interested in making their format look good, surely we must call into doubt the fact that their research is impartial. By carefully selecting and throwing away results, even an otherwise statistically correct study can be significantly skewed. While I don't know if this goes on at Philips (I hope not) and don't want to accuse them of anything, manipulation of statistics is a sort of industry standard. Judging by the kind of underhandedness that goes on at drug trials, I don't think we could trust a report published by a company with an interest in the outcome.

Good point. I agree with you, don't trust officially published reports from companies that have an interest in the conclusions. At the other hand, it is the only source which you have as an outsider. There is an audio standard war going on and funny to mention is that Philips was also involved in DVD-Audio for a small percentage. Cheap commercial trick to ensure business in the future.

For me, only listening related stuph do interest me and the mathematical explanation behind it. Theoretical there is no way of saying that the current digital standard, ie, 16 bits 44k1, is not good enough. Sampling theorem. But the sampling theorem assumes 2 things: ideal Nyquist filtering and infinite "bit-resolution". And 16 bits is far from infinite. In my humble opnion it has nothing to do with dynamic range but more with resolution and bandwidth. The established format (16/44k1) has a noise floor of 213 nV/sqrt(Hz) and this is quite high in comparison with 24/96 (576 pV/sqrt(Hz)) but still lower than a common audio amplifier.
Logical reasoning brings you from a to b, imagination brings you everywhere.

  • plonk420
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Is DVD Audio necessary ?
Reply #26
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Here is a good example of absolutely obvious differences that vanish under blind conditions : http://www.nytimes.com/library/tech/99/12/...les/23down.html

Code: [Select]
 Mr. Dunlavy has often gathered audio critics in his Colorado Springs lab for a demonstration.

omg, Colorado Springs lab...? where's that? i live there/here. O_O

  • Never_Again
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Is DVD Audio necessary ?
Reply #27
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omg, Colorado Springs lab...? where's that? i live there/here. O_O

Ah, Colorado Springs! The home of bigass server ... ^_^

  • Pio2001
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Is DVD Audio necessary ?
Reply #28
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omg, Colorado Springs lab...? where's that? i live there/here. O_O

According to http://www.stereophile.com/interviews/163/ , the lab is called Dunlavy Audio Labs

  • 2Bdecided
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Is DVD Audio necessary ?
Reply #29
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omg, Colorado Springs lab...? where's that? i live there/here. O_O

According to http://www.stereophile.com/interviews/163/ , the lab is called Dunlavy Audio Labs

That guy really knows what he's talking about!

  • fcmts
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Is DVD Audio necessary ?
Reply #30
Pio2001 wrote:
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Therefore, after a lossy compression, all high definition content will be eventually lost ! The first thing that any encoder will do is throwing away anything above 20 kHz, turning 96 kHz sample rate a waste, and anything below 16 bits, (at least during the music) turning the 24 bits definition a waste too.

I'm not sure about that. I couldn't open that 24/96WMA9Pro file with SoundForge7a with its entire resolution because there is a known bug (from Release Notes):
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Opening 24-bit WMA files results in the file being opened as 16-bit. We are aware of the issue and are working to resolve it.

...and Audacity doesn't work too. So, I tried to convert it first to a wave file but I couldn't either because I can't find a tool capable of it. I only made it by first encoding to WMA9Lossless and then using the wmal2pcm to obtain a wave file.
Analyzing its spectrum with Audacity we can see that there is still much above 20kHz. Forgive my english.

  • 2Bdecided
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Is DVD Audio necessary ?
Reply #31
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Analyzing its spectrum with Audacity we can see that there is still much above 20kHz. Forgive my english.

Did it relate to content in the original file?

The compression techniques used by WMA (which no one knows for sure) could allow for content beyond 20kHz, which is correlated to content below 20kHz, to be stored approximately with very little bitrate penalty.

It would be interesting to see what they are doing. It would be even more entertaining to ask MS why!

Cheers,
David.

  • fcmts
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Is DVD Audio necessary ?
Reply #32
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Analyzing its spectrum with Audacity we can see that there is still much above 20kHz. Forgive my english.

Did it relate to content in the original file?

I was talking about the result of:
DVD -> WAV -> WMA9 -> WMALL -> WAV
I can describe each step if you wish.

  • 2Bdecided
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Is DVD Audio necessary ?
Reply #33
I think I understand what you're doing - I was wondering exactly what the WMA9 encoder was doing, but I guess I can test this for myself.

I'm surprised no one else has tried what you're trying, for curiosity if nothing else. I guess people's dislike of MS and perceived lack of need for higher sampling rates has stopped anyone from spending any time on this. Still, if ogg or MPC announced support for 96k sampling, I bet everyone would want to test it! Either to prove how great it was, or how pointless it was.

Cheers,
David.

  • Pio2001
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Is DVD Audio necessary ?
Reply #34
All the music I buy is 44100 Hz or 48000 Hz, or copied from FM, or from vinyl, and I tested 48 vs 96 kHz vinyl recording without hearing a difference.
That's why I'm not very interested in 96 kHz compression. I've got no 96 kHz source.