What no one has mentioned about the prospect of multi channel audio is really quite significant. I think it's safe to say, that probably at least (at a guess) 98% of people who will be interested in it will have far from an ideal listening room.
If you think about it, the reflections and aucoustic resonances created from music coming from that many speakers would at the end of the day sound far worse than a well set up 2 channel hifi system. Unless someone is willing to go the the length of acoustic absorption and diffraction in thier room i fail to see the benefits of multi channel audio, it would just create a 'mess' of sound.
I consider myself a bit of an audiophile, i have some simple acoustic dampening on the walls of my listening room etc. but i can safely say there is no WAY i'm going to move to multi channel audio any time soon, the prospect of 192kHz 2 channel is far more inviting to me.
#19 - I tried that logic in another news comment somewhere around here... making a statement that either expressed or implied that this stuff has no way of competing with the likes of Aardvark, M-Audio (their pro cards anyway), MOTU, etc. I'm fairly certain it was me that Kris had to take a personal st@b at with his comment about "defending M-audio cards to the death." But I'm sorry, like it or not, a 24/96 pro card will still whip your 32/192 integrated setup's derriere, unless the motherboard manufacturers suddenly stop scrimping on DACs and such.
"While little is known outside enthusiast high fidelity circles, some DVD-A media and sampling are already shipping. Mitsubishi's newest line of DVD players uses the processor that supports DVD-A."
Unless I'm missing something here, you seem to be implying that DVD-A hardware and software is just reaching the market. Both DVD-A and SACD has had hardware on the market since 1999 from major electronics companies. These formats are not new at all and there is plenty of music available in both formats.
Don't get the Mitsubishi line either. Almost every DVD player sold for over $100 today supports DVD-A. There is no DVD-A "processor", just as there is no CD audio processor. There's nothing to decode except the encryption and then the digital signal is converted to analog for playback.
"$.75 codec + $1.00 PCB + same noisy PC power supply = ???" That is the problem with any new audio standard I've been told. Unless this formula is improved on then "you only get out of it what you put into it".
Becuase hardcore people will buy it first and enjoy it with their crazy setups. Eventually this will get cheaper and 'everyone' will have it. Then comes something else which the hardcore people can get their hands on. Then the cycle repeats.
Everyone with cheap 32" widescreen tv's a few years ago anyone? No didn't think so but it is cheap now.
btw, is the 8 channel azalia stuff designed to be used for 7.1 audio? or is the 8th channel a full bandwidth channel with a separate sub channel? or is it 8 channels total that can be used flexibly? (is that a word?)
CaptainSpectacular: All arguments made when we moved from cassette to compact disc. If it doesnt cost us any additional premium, does it really matter?
Eight bloody channels (who really has that many speakers hooked up to their system?) and bloated bandwidth that provides detail beyond the ability of human hearing to discern. Why do we care?
ultimately, i think for the vast majority of people, SACD and DVD-A are simply going to be ways for music to be presented in surround sound. I find it unlikely that the majority of the market is going to be able to hear the difference in sound quality, just like most people think MP3's sound just as good as CD's. in fact, i think a large portion of the people buying this technology won't even have an audio system good enough to even reproduce the improved sound quality.
Good points. I was trying to think of any reason why increasing the sample rate would help, there seems to be a reason, cause it does look better, but then I think that the only reason you need to sample faster is cause the frequency changes faster than can be measured.
Think about it, you say that if you don't sample enough you miss the peak of the sine wave. Sounds like good reasoning. But then again, the only reason why you would miss the peak is cause the frequency is changing too fast for the turrent sampling rate to graph correctly. Either way sounds reasonable.
Well, also, just about all I've said about SACD was on Sony's website when SACD first debuted. They along with Philips explained why they when this route instead of simply increasing the resolution. Their first player also employed some really neat tricks as well to counter noise problems when switching from 0 to 1, and also using current instead of voltage in most stages since current is more stable.
What convinced me is the fact that just about all cd players use the delta/sigma converter to reproduce sound using the 1 bit strategy. So Sony and Philips said let's just store it that way to begin with, since according to them music nowadays is recorded that way, though that sounds unlikely.
Good point about the picture. Most of the time it's easier to represent all colors with just blue, green and red. Monitors, tv's, and LCD and DLP projectors do this. What DVD audio or Intel says though is it's better to make a monitor with 4.3 billion different color tubes to each represent 32 bit color instead of using on and off timing between the tubes, LCD pixels, or the color wheel with on and off of a DLP's mirrors. Which implementation sounds better/easier/more realistic to work to you?
That explanation of SACD was great, and very interesting - a lot like an audio version of dithering! One thing I'm concerned with slightly is how does it cope with large dynamic ranges (for instance orchestral music)? A very quiet signal (thousands or tens of thousands of times below the max) would have to rely on detecting that one part in 10000 in an otherwise 50-50 mix of ups and downs. You'd probably need 10000 1bit samples to do that. In comparison to 24 bit and 32 bit formats it gets (theoretically) worse, as these can represent within one of their samples down to millionths or billionths of the maximum volume. However I _think_ those correspond to -120dB and -180dB attenuations respectively, so unless you're listening to a rocket launch interspersed with quiet string instruments... :)
--[There is no point to increasing the sampling rate though in normal PCM formats. You can say that the sine wave looks smoother since you are graphing it more precise, but it makes no difference]--
I don't think there'd be much point going above Azalia's 192kHz, but sampling a sine-wave with only about 5 points per cycle does have some effect because although you've got enough to define the _frequency_, the samples sometimes miss the peak of the sine by a little bit, changing its reconstructed amplitude. They do this periodically as the sine frequency beats with the nearest subharmonic of the sampling frequency. This beat frequency is (annoyingly!) quite often back down in the audible range, so I think that explains why some hi-fi nuts can hear it even when the sampling is 44 or 88kHz.
Sprockkets, thank you for that wonderful treatise on SACD. It seems to boil down to dramatically increasing temporal resolution to make up for shallow bit depth.
Those of us who are into imaging can see the tradeoff: a 320x240x32bit image is still low resolution, even though every pixel can take on one of four billion values.
On the other hand, if we increase the resolution hundredfold in each direction (to 32000x24000 pixels), each pixel can be a dot of a solid color but they're so small that a group of them can represent any shade you'd like.
The only problem with using digital output for SACD or DVD-A is that.. you can't. SPDIF is defined for 24/96 stereo max, and DVD-A's are 24/192 stereo, or 24/96 in 4-6 channel (4.0, 4.1, 5.0 or 5.1). SACD is "weird" enough in and of itself that I don't think ANY receiver can decode it. The possible exception is the Pioneer Elite series which have a firewire input from compatible DVD players for audio. Now I'm no audiophile, but it strikes me as, well, efficient to keep the signal in digital format until the last possible stage..
"Since you can't hear over this what is the point?" - I think as someone mentioned earlier; although you cant audibly detect it, it does affect other frequencies you can* hear.
As far as playing DVD or SACD on PC; i think to some extent things do converge this way a little - look at how many people use their laptops this way. Furthermore, most decent motherboards and certainly every board with 8 channel output uses optical outputs with the intention you output to a receiver or something fairly capable.
Direct Stream digital addresses the issues of quantization errors and decimation due to first off recording in a 16 bit format to decoding. The best way to represent music is the simplest way. Instead of graphing music in 16 or 32 bit resolution, DSD samples the music at an extreme rate then gives a 1 if the value at that time went up or 0 if it went down.
A way to explain it is you can either try in vain to have 65,536 (now 16,777,216 with 24 bit and even 4,294,967,296 with 32 bit) different voltages reproduced in the analog output or you can turn the voltage on and off fast enough to make the different voltage levels necessary. It's like turning on and off the pixels in LCD displays to generate other colors, or turning on and off the power switch to a light to get the desired light level.
This problem was discovered early on with cd players. They had 16 bit d/a converters which were poor quality. It was much easier and with much higher quality to change the 16 bit format into a 1 bit format. Nearly all cd players do this except for the so called bur brown 16 or 32 bit decoders which claim to be better than the usual 1 bit converters.
This is the advantage of SACD: It gets rid of the resampling and conversion of 16 bit to 1 bit. It simply is recorded that way and stored that way.
There is no point to increasing the sampling rate though in normal PCM formats. You can say that the sine wave looks smoother since you are graphing it more precise, but it makes no difference, cause you sample the signal fast enough to define the full 20-20k Hz that people can hear, though most can't hear over 18k.
For instance, if the frequency of the wave changes from + to - only 30 times a second, the all you need to make sure you get it right is 30 times 2, plus a little more for safety. If you sample it any more than necessary you are simply wasting data because it will also report the same 30 Hz. But if it changes 100 times a second, then you will not see this cause you are not sampling enough. You can notice this cause when you record music at only 22k sampling rate, it sound dull because you are missing the higher frequencies that make it sound bright and clean.
I also get a kick of how to properly use these new formats you have to have systems that can reproduce sound over 20k Hz. Since you can't hear over this what is the point? Moreover, it seems that while we have higer end formats coming out, people are claiming that the cd and such are going away in favor of music downloading. Great, the quality of that music is disgusting.
There really is no point also to playing DVD or SACD audio on a PC. A computer with the many frequencies being generated internally makes any analog output sound bad compared to it being outputed digitally then decoded in a real audio receiver. But what is nice about SACD is that you can still rip the cd part of the disc if it is a hybrid and then listen to the SACD part in a proper player.
Actually I guess that's an encoding issue anyway. Seeing as we can send signals at 10Mbps through wires with no trouble, 192kHz isn't at all wasteful for the output. On the DVD itself you might want to use a form of high-frequency MP3ing if you wanted to get more on there.
Sorry I wasn't explaining my line of thought. I know that increasing the sampling rate beyond 44kHz improves the quality of the lower frequencies because they can then be represented more accurately as sine-waves rather than blocky things. I was just wondering if there could be a completely different way to improve the accuracy of the lower frequencies (a direct representation as a curve rather than a discrete set of samples, for instance), which is how MP3 works, at a lower level of fidelity.
I've posted this before, but something to remember about those frequencies you can't hear- they do affect the frequencies you CAN hear.
If you've every heard music on a more accurate, flat response Hi-Fi system that can actually produce those frequencies (and not on MP3s blared through Klipsch speakers) you would hear depth, clarity and a three dimensional soundstage. The first time I listened to music like that, from an analog source as well, I was completley floored, it was not unlike the first time I saw HD television.
I just hope that these 8 channel devices come with some kind of self-calibration because most folks don't even know how to set up a 2.1 system to be accurate.
Surely after a certain point, your ears don't get any better? I mean 192kHz includes a load of frequencies only your cat can hear. While I don't argue that it wouldn't be cool to have a button on your PC that could deter your cat on demand, I'm wondering if the next stage from this shouldn't be an MP3-like format that concentrates on encoding the frequencies we _can_ hear better. Perhaps it could even be decoded to many different raw sampling rates dependant on the hardware... it'd take up less room too.
I don't think either DVD-A or SACD will catch on until there are mobile audio systems that support those formats. I listen to far more music in my car than I do at home or work. The Acura TL offers DVD-A support so hopefully it will soon spread to other manufacturers and the aftermarket. I have a few DVD-A's and they sound excellent through my JVC DVD player. R.E.M.'s "Automatic for the People" is just wonderful in DVD-A.
Of course, DVD-A (and maybe others) has content "protection" so you can forget ripping the music you paid for to your own hard disk for your own personal listening pleasure that is within your fair use rights which the RIAA says you don't really have. If it weren't for that BS, I'd be more excited about the new high bandwidth audio formats.
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KristopherKubicki - Tuesday, June 15, 2004 - link
I have two ears and HD-600s. I think audio was meant for 2 channels :)Kristopher
CoZMoSiS - Tuesday, June 15, 2004 - link
What no one has mentioned about the prospect of multi channel audio is really quite significant. I think it's safe to say, that probably at least (at a guess) 98% of people who will be interested in it will have far from an ideal listening room.If you think about it, the reflections and aucoustic resonances created from music coming from that many speakers would at the end of the day sound far worse than a well set up 2 channel hifi system. Unless someone is willing to go the the length of acoustic absorption and diffraction in thier room i fail to see the benefits of multi channel audio, it would just create a 'mess' of sound.
I consider myself a bit of an audiophile, i have some simple acoustic dampening on the walls of my listening room etc. but i can safely say there is no WAY i'm going to move to multi channel audio any time soon, the prospect of 192kHz 2 channel is far more inviting to me.
jliechty - Monday, June 14, 2004 - link
#19 - I tried that logic in another news comment somewhere around here... making a statement that either expressed or implied that this stuff has no way of competing with the likes of Aardvark, M-Audio (their pro cards anyway), MOTU, etc. I'm fairly certain it was me that Kris had to take a personal st@b at with his comment about "defending M-audio cards to the death." But I'm sorry, like it or not, a 24/96 pro card will still whip your 32/192 integrated setup's derriere, unless the motherboard manufacturers suddenly stop scrimping on DACs and such.Pariah - Monday, June 14, 2004 - link
"While little is known outside enthusiast high fidelity circles, some DVD-A media and sampling are already shipping. Mitsubishi's newest line of DVD players uses the processor that supports DVD-A."Unless I'm missing something here, you seem to be implying that DVD-A hardware and software is just reaching the market. Both DVD-A and SACD has had hardware on the market since 1999 from major electronics companies. These formats are not new at all and there is plenty of music available in both formats.
Don't get the Mitsubishi line either. Almost every DVD player sold for over $100 today supports DVD-A. There is no DVD-A "processor", just as there is no CD audio processor. There's nothing to decode except the encryption and then the digital signal is converted to analog for playback.
DAPUNISHER - Sunday, June 13, 2004 - link
"$.75 codec + $1.00 PCB + same noisy PC power supply = ???" That is the problem with any new audio standard I've been told. Unless this formula is improved on then "you only get out of it what you put into it".
Koing - Sunday, June 13, 2004 - link
Why?Becuase hardcore people will buy it first and enjoy it with their crazy setups. Eventually this will get cheaper and 'everyone' will have it. Then comes something else which the hardcore people can get their hands on. Then the cycle repeats.
Everyone with cheap 32" widescreen tv's a few years ago anyone? No didn't think so but it is cheap now.
Koing
CaptainSpectacular - Sunday, June 13, 2004 - link
kristopher - point taken.btw, is the 8 channel azalia stuff designed to be used for 7.1 audio? or is the 8th channel a full bandwidth channel with a separate sub channel? or is it 8 channels total that can be used flexibly? (is that a word?)
KristopherKubicki - Sunday, June 13, 2004 - link
CaptainSpectacular: All arguments made when we moved from cassette to compact disc. If it doesnt cost us any additional premium, does it really matter?Kristopher
madgonad - Sunday, June 13, 2004 - link
Eight bloody channels (who really has that many speakers hooked up to their system?) and bloated bandwidth that provides detail beyond the ability of human hearing to discern. Why do we care?CaptainSpectacular - Saturday, June 12, 2004 - link
ultimately, i think for the vast majority of people, SACD and DVD-A are simply going to be ways for music to be presented in surround sound. I find it unlikely that the majority of the market is going to be able to hear the difference in sound quality, just like most people think MP3's sound just as good as CD's. in fact, i think a large portion of the people buying this technology won't even have an audio system good enough to even reproduce the improved sound quality.sprockkets - Saturday, June 12, 2004 - link
Good points. I was trying to think of any reason why increasing the sample rate would help, there seems to be a reason, cause it does look better, but then I think that the only reason you need to sample faster is cause the frequency changes faster than can be measured.Think about it, you say that if you don't sample enough you miss the peak of the sine wave. Sounds like good reasoning. But then again, the only reason why you would miss the peak is cause the frequency is changing too fast for the turrent sampling rate to graph correctly. Either way sounds reasonable.
Well, also, just about all I've said about SACD was on Sony's website when SACD first debuted. They along with Philips explained why they when this route instead of simply increasing the resolution. Their first player also employed some really neat tricks as well to counter noise problems when switching from 0 to 1, and also using current instead of voltage in most stages since current is more stable.
What convinced me is the fact that just about all cd players use the delta/sigma converter to reproduce sound using the 1 bit strategy. So Sony and Philips said let's just store it that way to begin with, since according to them music nowadays is recorded that way, though that sounds unlikely.
Good point about the picture. Most of the time it's easier to represent all colors with just blue, green and red. Monitors, tv's, and LCD and DLP projectors do this. What DVD audio or Intel says though is it's better to make a monitor with 4.3 billion different color tubes to each represent 32 bit color instead of using on and off timing between the tubes, LCD pixels, or the color wheel with on and off of a DLP's mirrors. Which implementation sounds better/easier/more realistic to work to you?
stephenbrooks - Saturday, June 12, 2004 - link
That explanation of SACD was great, and very interesting - a lot like an audio version of dithering! One thing I'm concerned with slightly is how does it cope with large dynamic ranges (for instance orchestral music)? A very quiet signal (thousands or tens of thousands of times below the max) would have to rely on detecting that one part in 10000 in an otherwise 50-50 mix of ups and downs. You'd probably need 10000 1bit samples to do that. In comparison to 24 bit and 32 bit formats it gets (theoretically) worse, as these can represent within one of their samples down to millionths or billionths of the maximum volume. However I _think_ those correspond to -120dB and -180dB attenuations respectively, so unless you're listening to a rocket launch interspersed with quiet string instruments... :)--[There is no point to increasing the sampling rate though in normal PCM formats. You can say that the sine wave looks smoother since you are graphing it more precise, but it makes no difference]--
I don't think there'd be much point going above Azalia's 192kHz, but sampling a sine-wave with only about 5 points per cycle does have some effect because although you've got enough to define the _frequency_, the samples sometimes miss the peak of the sine by a little bit, changing its reconstructed amplitude. They do this periodically as the sine frequency beats with the nearest subharmonic of the sampling frequency. This beat frequency is (annoyingly!) quite often back down in the audible range, so I think that explains why some hi-fi nuts can hear it even when the sampling is 44 or 88kHz.
Odeen - Saturday, June 12, 2004 - link
Sprockkets, thank you for that wonderful treatise on SACD. It seems to boil down to dramatically increasing temporal resolution to make up for shallow bit depth.Those of us who are into imaging can see the tradeoff: a 320x240x32bit image is still low resolution, even though every pixel can take on one of four billion values.
On the other hand, if we increase the resolution hundredfold in each direction (to 32000x24000 pixels), each pixel can be a dot of a solid color but they're so small that a group of them can represent any shade you'd like.
The only problem with using digital output for SACD or DVD-A is that.. you can't. SPDIF is defined for 24/96 stereo max, and DVD-A's are 24/192 stereo, or 24/96 in 4-6 channel (4.0, 4.1, 5.0 or 5.1). SACD is "weird" enough in and of itself that I don't think ANY receiver can decode it.
The possible exception is the Pioneer Elite series which have a firewire input from compatible DVD players for audio. Now I'm no audiophile, but it strikes me as, well, efficient to keep the signal in digital format until the last possible stage..
KristopherKubicki - Saturday, June 12, 2004 - link
Sprockets; all good points."Since you can't hear over this what is the point?" - I think as someone mentioned earlier; although you cant audibly detect it, it does affect other frequencies you can* hear.
As far as playing DVD or SACD on PC; i think to some extent things do converge this way a little - look at how many people use their laptops this way. Furthermore, most decent motherboards and certainly every board with 8 channel output uses optical outputs with the intention you output to a receiver or something fairly capable.
But yes, i basically agree with all your points.
Kristopher
sprockkets - Saturday, June 12, 2004 - link
Direct Stream digital addresses the issues of quantization errors and decimation due to first off recording in a 16 bit format to decoding. The best way to represent music is the simplest way. Instead of graphing music in 16 or 32 bit resolution, DSD samples the music at an extreme rate then gives a 1 if the value at that time went up or 0 if it went down.A way to explain it is you can either try in vain to have 65,536 (now 16,777,216 with 24 bit and even 4,294,967,296 with 32 bit) different voltages reproduced in the analog output or you can turn the voltage on and off fast enough to make the different voltage levels necessary. It's like turning on and off the pixels in LCD displays to generate other colors, or turning on and off the power switch to a light to get the desired light level.
This problem was discovered early on with cd players. They had 16 bit d/a converters which were poor quality. It was much easier and with much higher quality to change the 16 bit format into a 1 bit format. Nearly all cd players do this except for the so called bur brown 16 or 32 bit decoders which claim to be better than the usual 1 bit converters.
This is the advantage of SACD: It gets rid of the resampling and conversion of 16 bit to 1 bit. It simply is recorded that way and stored that way.
There is no point to increasing the sampling rate though in normal PCM formats. You can say that the sine wave looks smoother since you are graphing it more precise, but it makes no difference, cause you sample the signal fast enough to define the full 20-20k Hz that people can hear, though most can't hear over 18k.
For instance, if the frequency of the wave changes from + to - only 30 times a second, the all you need to make sure you get it right is 30 times 2, plus a little more for safety. If you sample it any more than necessary you are simply wasting data because it will also report the same 30 Hz. But if it changes 100 times a second, then you will not see this cause you are not sampling enough. You can notice this cause when you record music at only 22k sampling rate, it sound dull because you are missing the higher frequencies that make it sound bright and clean.
I also get a kick of how to properly use these new formats you have to have systems that can reproduce sound over 20k Hz. Since you can't hear over this what is the point? Moreover, it seems that while we have higer end formats coming out, people are claiming that the cd and such are going away in favor of music downloading. Great, the quality of that music is disgusting.
There really is no point also to playing DVD or SACD audio on a PC. A computer with the many frequencies being generated internally makes any analog output sound bad compared to it being outputed digitally then decoded in a real audio receiver. But what is nice about SACD is that you can still rip the cd part of the disc if it is a hybrid and then listen to the SACD part in a proper player.
stephenbrooks - Saturday, June 12, 2004 - link
Actually I guess that's an encoding issue anyway. Seeing as we can send signals at 10Mbps through wires with no trouble, 192kHz isn't at all wasteful for the output. On the DVD itself you might want to use a form of high-frequency MP3ing if you wanted to get more on there.stephenbrooks - Saturday, June 12, 2004 - link
Sorry I wasn't explaining my line of thought. I know that increasing the sampling rate beyond 44kHz improves the quality of the lower frequencies because they can then be represented more accurately as sine-waves rather than blocky things. I was just wondering if there could be a completely different way to improve the accuracy of the lower frequencies (a direct representation as a curve rather than a discrete set of samples, for instance), which is how MP3 works, at a lower level of fidelity.dgrady76 - Saturday, June 12, 2004 - link
I've posted this before, but something to remember about those frequencies you can't hear- they do affect the frequencies you CAN hear.If you've every heard music on a more accurate, flat response Hi-Fi system that can actually produce those frequencies (and not on MP3s blared through Klipsch speakers) you would hear depth, clarity and a three dimensional soundstage. The first time I listened to music like that, from an analog source as well, I was completley floored, it was not unlike the first time I saw HD television.
I just hope that these 8 channel devices come with some kind of self-calibration because most folks don't even know how to set up a 2.1 system to be accurate.
stephenbrooks - Saturday, June 12, 2004 - link
Surely after a certain point, your ears don't get any better? I mean 192kHz includes a load of frequencies only your cat can hear. While I don't argue that it wouldn't be cool to have a button on your PC that could deter your cat on demand, I'm wondering if the next stage from this shouldn't be an MP3-like format that concentrates on encoding the frequencies we _can_ hear better. Perhaps it could even be decoded to many different raw sampling rates dependant on the hardware... it'd take up less room too.Oxonium - Saturday, June 12, 2004 - link
I don't think either DVD-A or SACD will catch on until there are mobile audio systems that support those formats. I listen to far more music in my car than I do at home or work. The Acura TL offers DVD-A support so hopefully it will soon spread to other manufacturers and the aftermarket. I have a few DVD-A's and they sound excellent through my JVC DVD player. R.E.M.'s "Automatic for the People" is just wonderful in DVD-A.jliechty - Saturday, June 12, 2004 - link
Of course, DVD-A (and maybe others) has content "protection" so you can forget ripping the music you paid for to your own hard disk for your own personal listening pleasure that is within your fair use rights which the RIAA says you don't really have. If it weren't for that BS, I'd be more excited about the new high bandwidth audio formats.artifex - Friday, June 11, 2004 - link
for the sake of completeness, doesn't CD+G allow for still pictures?Apologiliac - Friday, June 11, 2004 - link
I think this will be very exciting when we see regular music cd's of today shipping in DVD-a format