Hi guys
Something that's been bothering me for a while... Please somebody correct me immediately if I am wrong on this but I'm pretty sure the general consensus on this board is that nobody (or very close to nobody) can tell the difference between a properly encoded 320kbps mp3 and the original cd, right?
So the difference between a normal cd and a "high quality" SACD is likely to be even more difficult to distinguish, likely going completely beyond any human's ability to tell the difference.
So what the hell is the point of SACDs!?
Please somebody explain this to me.
Sam
The higher sampling rate and bit-depth makes it harder to create masters that clip on the medium (that the music industry so loves to do). The masters are also generally better than CD masters. Also multi-channel is a compelling argument.
So what the hell is the point of SACDs!?
If you can make some people believe that SACDs are worth purchasing you can possibly make more bucks by releasing music on SACDs as well. That's the main idea.
I'm not denying that "high-res" formats may also benefit customers, too (multi channel audio, the warm fuzzy feeling you get if you believe you can "hear the details beyond 20 kHz" etc)
The higher sampling rate and bit-depth makes it harder to create masters that clip on the medium (...)
...and by bit-depth you probably mean signal-to-noise ratio in the audible band. These terms are not always interchangable. In this case they aren't since SACDs store 1-bit-signals.
Cheers!
SG
for the mastering technique and for multi-channel is worthwhile...
but I don't think SACD will ever catch...
Hi guys
Something that's been bothering me for a while... Please somebody correct me immediately if I am wrong on this but I'm pretty sure the general consensus on this board is that nobody (or very close to nobody) can tell the difference between a properly encoded 320kbps mp3 and the original cd, right?
So the difference between a normal cd and a "high quality" SACD is likely to be even more difficult to distinguish, likely going completely beyond any human's ability to tell the difference.
So what the hell is the point of SACDs!?
Please somebody explain this to me.
Sam
DSD was originally envisioned and developed as a high-quality archiving format for record companies, one that could be easily converted to consumer format -- e.g. Redbook PCM. Then somewhere along the line it was decided that it should be given its own consumer delivery medium -- the Super Audio CD -- even though this requires a new player. Some speculate that this had to do with expiration of CD patents, but I don't know about that.
What's always been interesting to me is that no actual scientifically-designed tests were ever published at the time to demonstrate the supposed 'obvious' audible superiority of DSD in the first place. The only evidence ever published for that came later, with some dubious papers from Japan (and even there, the effect wasn't really 'obvious' statistically). The audible difference finding was not replicable by another Japanese group, and a recent report of a long-term SACD vs CD listening test also failed to find significant difference
http://www.hydrogenaudio.org/forums/index....mp;#entry515556 (http://www.hydrogenaudio.org/forums/index.php?showtopic=57406&st=0&p=515556&#entry515556)
There are good arguments to make for having archive formats be 'hi rez', but there's no intrinsic reason for the existence of SACDs. Their value , IMO lay in fostering 'audiophile' remastering, and in providing multichannel output.
CD Audio is a poor format anyway, but most people probably won't realise this.
For me, the main attraction of SACD and DVD-A is multichannel audio. Also DVD-A uses a proper file system and error correction so it's much easier to rip DVD-As. SACDs are proprietary so they don't interest me one bit.
So what the hell is the point of SACDs!?
Having a closed system with built-in copy protection to taunt honest customers.
CD Audio is a poor format anyway, but most people probably won't realise this.
I guess I'm one of them. Care to explain?
CD Audio is a poor format anyway, but most people probably won't realise this.
Based on what?
for the mastering technique and for multi-channel is worthwhile...
What "mastering technique" are you talking about, the one where the CD layer is intentionally mastered to sound poorer than the SACD layer?
CD Audio is a poor format anyway, but most people probably won't realise this.
For me, the main attraction of SACD and DVD-A is multichannel audio. Also DVD-A uses a proper file system and error correction so it's much easier to rip DVD-As. SACDs are proprietary so they don't interest me one bit.
Hindsight is always 20-20. Let's send you back in a time machine so you can tell Sony and Philips what a huge mistake they made.
What bothers me that you have not found the search button. This subject has been discussed to death on this forum.
Triza
Hi guys
Something that's been bothering me for a while... Please somebody correct me immediately if I am wrong on this but I'm pretty sure the general consensus on this board is that nobody (or very close to nobody) can tell the difference between a properly encoded 320kbps mp3 and the original cd, right?
So the difference between a normal cd and a "high quality" SACD is likely to be even more difficult to distinguish, likely going completely beyond any human's ability to tell the difference.
So what the hell is the point of SACDs!?
Please somebody explain this to me.
Sam
What "mastering technique" are you talking about, the one where the CD layer is intentionally mastered to sound poorer than the SACD layer?
No, there are very well mastered CD's out there - we don't need SACD's over these ones. I mean, the ones intentionally pushed to the full digital scale in CD, they could not do the same technique with SACD.
they could not do the same technique with SACD
Why is that?
EDIT #1:
for the mastering technique and for multi-channel is worthwhile...
You gave me the impression that some special technique
could be employed for SACD but could
not for CDDA.
One might argue that the ability to add heavy compression to CDDA is a good thing (at least it allows for greater possibilities).
EDIT #2: (Wrong quote used for EDIT #1)
they could not do the same technique with SACD
Why is that?
details about the Scarlet Book-mandated differences in DSD vs CD mastering, in this DSD ADC user manual (see p 10 and onwards for example):
http://www.grimmaudio.com/Manual%20AD1.pdf (http://www.grimmaudio.com/Manual%20AD1.pdf)
elsewhere I see :
http://www.audioasylum.com/cgi/t.mpl?f=hirez&m=237418 (http://www.audioasylum.com/cgi/t.mpl?f=hirez&m=237418)
0dBfs = -6dB 'SACD' or another way; The nominal maximum level for an SACD is 6dB below PCM's absolute maximum of 0dBfs.
The maximum legal limit of an SACD's amplitude is +3.1 dB SACD or -2.9dBfs PCM. The mentioned 'Scarlet Book' also sets limits for ultra-sonic noise and DC offset.
What I actually said is that I hear problems with pushing levels up to the +3.1 maximum level and prefer to keep my maximum to 0dB SACD, with occasional peaks going up to about +1.5 dB SACD.
Really fast transients (essentially inaudible) are not really the problem; it's when the peak duration is around 200 samples or longer that it starts to become noticeable.
There is nothing gentle or soft about signals that exceed the +3.1 level; it's illegal because it is gross over-modulation of a system that behaves best with 50% modulation (-6dB), but will tolerate 76% modulation (-3.1dB) - just don't spend any 'musically significant time' at that latter level...
CD Audio is a poor format anyway, but most people probably won't realise this.
I guess I'm one of them. Care to explain?
Unreliable extraction for a start. It is completely acceptable in the specification for there to be loss when extracting CD Audio. It has a silly, low and fixed sample rate (44.1kHz). No reference average sound pressure level set in the spec (which allowed the loudness war).
Yes, some of this is hindsight but Dolby got a lot of this right when developing AC3 at around the same time.
Yes, some of this is hindsight but Dolby got a lot of this right when developing AC3 at around the same time.
Apples and oranges on so many levels.
I didn't see AC3 delivered on a 12cm disc when it came out; not to mention that there's about a 10-year difference between the release of the two formats.
@krabapple: thanks for the info.
CD Audio is a poor format anyway, but most people probably won't realise this...
How can they realise this??!!
...For me, the main attraction of SACD and DVD-A is multichannel audio. Also DVD-A uses a proper file system and error correction so it's much easier to rip DVD-As. SACDs are proprietary so they don't interest me one bit.
Have you ripped DVD-A?!
Perhaps you ripped the DVD-V audio also present in the DVD-A disc instead.
For me, the main attraction of SACD and DVD-A is multichannel audio. Also DVD-A uses a proper file system and error correction so it's much easier to rip DVD-As. SACDs are proprietary so they don't interest me one bit.
DVD-Audio discs are much more of a PITA to rip because of DRM. And, uh, all those medias are proprietary. CD-DA, DVD-A, SACD, all of them.
DVD-A can be completely reliably and easily extracted from the disc. It might need to be decrypted if it's a commercial disc but I don't just worry about ripping commercial discs.
Proprietary was the wrong word but you know what I mean. You will only ever be able to buy an SACD player, not a general purpose SACD drive.
People can realise that CD is a poor format when they try to extract audio from a disc with a normal ripper, like iTunes or something. No errors, iTunes thinks it went fine, but it could be riddled with clicks, pops and other errors. Could you imagine copying your backed up files from a data CD and having data loss but absolutely no warning of it?
This is why a lot of people use EAC, because it attempts to compensate for the shortcomings of CD audio by using several techniques.
Oh come on borbus. CD was designed for playing on technology that was around at the end of the 1970s.
The reason there are "issues" with copying it bit-perfectly at high speed (though AcurateRip suggests it's easy to do on most drives with burst copy these days) is because it wasn't designed for this purpose.
It's like saying that books are poor because they don't always OCR correctly!
As for the original topic, please click on the "FAQ" link at the top right of the page and find the appropriate threads. There are several.
Cheers,
David.
DVD-A can be completely reliably and easily extracted from the disc. It might need to be decrypted if it's a commercial disc but I don't just worry about ripping commercial discs.
First, if you don't rip commercial discs, I don't know what you rip. If you're talking only about the intrinsic qualities of the medium, you might as well go for DVD-ROM with simple files on them.
Second, how do you easily extract and decode MLP content without paying a couple thousand dollars or pirating software? Even with pirated software I don't know of an easy solution. Are you sure you're not talking about DVD-Video with musical content? Even if you are, that medium isn't perfect either. Chapter timings are often imprecise, especially with titles that have several audio tracks that are slightly different in duration. And by the way, extracting content from DVD-based mediums is illegal in many countries.
Oh come on borbus. CD was designed for playing on technology that was around at the end of the 1970s.
The reason there are "issues" with copying it bit-perfectly at high speed (though AcurateRip suggests it's easy to do on most drives with burst copy these days) is because it wasn't designed for this purpose.
It's like saying that books are poor because they don't always OCR correctly!
As for the original topic, please click on the "FAQ" link at the top right of the page and find the appropriate threads. There are several.
Cheers,
David.
I think the point still stands that it'd be nice to have a new format with a real file system where we could simple copy music files from a folder instead of a complicated ripping procedure. This will never happen because the record industry is hell bent on DRM.
I think the point still stands that it'd be nice to have a new format with a real file system where we could simple copy music files from a folder instead of a complicated ripping procedure. This will never happen because the record industry is hell bent on DRM.
We have lossless downloads from some companies, and DRM-free mp3s from others. If it's CSS-free (or you don't care about hacking) then DVD-V is a pretty easy way of sharing and storing Linear PCM audio data, just not at 44.1kHz.
If DVD-A had become the
de facto audio standard, I guess MLP wouldn't be as out of reach as it is now, just like the more complex MPEG-2 video compression is easily within reach because it had to be.
If something like DVB-CPCM became widely supported, then it wouldn't matter if the content had DRM or not - you could still use it in all your devices, back it up, take it to the beach etc - just not share it on the net (easily).
But, so far, the market place isn't very interested in these things, so we have what we have!
Cheers,
David.
Oh come on borbus. CD was designed for playing on technology that was around at the end of the 1970s.
Historical facts seem to be lost on him.
CD Audio is a poor format anyway, but most people probably won't realise this.
Yup, it is old, made to be plaied without much pain.
But today we don't need to dispute about physical medium anymore: wav and mp3 (on a data CD/DVD/HD/flash) are the way to go . Who needs SACD or DVD-A?
It has a silly, low and fixed sample rate (44.1kHz).
44.1 kHz is low? The way I see it, 44.1 kHz is a totally acceptable sampling rate for reproduction purposes. For manipulatory purposes, I have no reservations about working with 88.2 kHz, 96 kHz, 176.4 kHz or 192 kHz (particularly helpful when leveraging too much TC/TE, as I tend to do too frequently), but the audible differences between a 44.1 kHz master and a 192 kHz master will be slight to essentially nonexistent on most playback systems. I think even 40 kHz would have been easily acceptable for a consumer-grade format considering the qualities of Nyquist filters.
As for the original question: why SACDs? My answer to that would be: why not?
As for the original question: why SACDs? My answer to that would be: why not?
They and the equipment you need are more expensive, even to produce, and they are harder to rip than CD, with all their DRM.
apart from DRM, they could substitute CD in the future, why not?... but in the near future we will not need to care about physical media anymore.
I still buy CD, but only to rip them.
Hi guys
Something that's been bothering me for a while... Please somebody correct me immediately if I am wrong on this but I'm pretty sure the general consensus on this board is that nobody (or very close to nobody) can tell the difference between a properly encoded 320kbps mp3 and the original cd, right?
So the difference between a normal cd and a "high quality" SACD is likely to be even more difficult to distinguish, likely going completely beyond any human's ability to tell the difference.
So what the hell is the point of SACDs!?
Please somebody explain this to me.
Sam
DSD was originally envisioned and developed as a high-quality archiving format for record companies, one that could be easily converted to consumer format -- e.g. Redbook PCM.
From what I've seen, it was originally proposed as a lower cost alternative to PCM. Once it didn't work out for that, then it was suggested as a higher quality option.
Now I think its mostly an excuse to slip more DRM into the market.
CD Audio is a poor format anyway, but most people probably won't realise this...
How can they realise this??!!
...For me, the main attraction of SACD and DVD-A is multichannel audio. Also DVD-A uses a proper file system and error correction so it's much easier to rip DVD-As. SACDs are proprietary so they don't interest me one bit.
Have you ripped DVD-A?!
Perhaps you ripped the DVD-V audio also present in the DVD-A disc instead.
IME, you can rip some (not all) commercial DVD-A, but 'easy' isn't the word I'd use to describe the process.
Apparently Borbus thinks that back in the late 70's, CD developers should have anticipated 1) the desire for
bit-perfect copying (and facilitated it), 2) reconstruction filtering issues near 20 kHz (I presume that's his objection to that baseband limit, and not some idea that we actually hear much of anything beyond that)
and 3) the exploitation of the format to *reduce* dynamic range, even though at the time one of the prime advertised reasons for buying CD was to finally be able to reproduce the actual dynamic range of recordings, at playback.
Hold on... Since when do we care when technology was invented? Back in the early 90s MP3 was absolutely amazing... is it still? No.
When the mobile telephone was introduced, did people shake their head and say "no.. back when Bell invented the phone we wouldn't have needed mobile phones so we don't now". Of course not.
The original question was "Why SACDs?" and I interpreted that to be "Why drop an older technology for a newer technology?" My answer is simple, in THIS day and age, CD Audio just doesn't cut it. I don't care how perfect it was back in the 70s.
SACD is a great way to waste bits and make a sub-par audio format, compared with conventional PCM. Ok, it can sound as good as hi-res PCM, but it's still a stupid way of storing digital audio because it mostly carries high frequency noise that has to be removed in order for the format to be usable. It's a marketing-driven format which has little sense from a technological point of way.
Hi-res PCM (DVD-A) is much more efficient and better from an objective quality point of view.
As to CD not being good enough the only drawback it has is not being multi-channel. It can be easily ripped (try to rip any SACD or DVD-A disk you can find), and quality is good enough. We can't perceive all the extended bandwidth and dynamic range that hi-res formats provide. They are just selling numbers.
SACD is a great way to waste bits and make a sub-par audio format, compared with conventional PCM. Ok, it can sound as good as hi-res PCM, but it's still a stupid way of storing digital audio because it mostly carries high frequency noise that has to be removed in order for the format to be usable.
Reconstruction of DSD really isn't all that difficult. Where did you come up with this nonsense?
Hi-res PCM (DVD-A) is much more efficient and better from an objective quality point of view.
From the document that krabapple referenced:
Practice so far shows that DSD is at least as sonically transparent as 192kHz/24 bit and better than 96kHz/24bit. However, one channel of DSD takes up only 2.8Mbit/s, whereas one channel of 192kHz/24bit takes up 4.6Mbit/s.
So, how exactly is DVD-A more efficient or better from an "objective quality" point of view than SACD?
Well, we are going DVD-A vs SACD here, after we have understood that both them are useless.
Great
Only I would really like to understand what "is at least as sonically transparent" means.
even a PCM 44Khz/16bit is "at least as sonically transparent as" 192kHz/24 bit and it need much less space.
Isn't it?
Point taken.
BTW, I'm not a believer of high resolution formats when it comes to reproducing 2-channel audio.
Hi-res PCM (DVD-A) is much more efficient and better from an objective quality point of view.
From the document that krabapple referenced:
Practice so far shows that DSD is at least as sonically transparent as 192kHz/24 bit and better than 96kHz/24bit. However, one channel of DSD takes up only 2.8Mbit/s, whereas one channel of 192kHz/24bit takes up 4.6Mbit/s.
So, how exactly is DVD-A more efficient or better from an "objective quality" point of view than SACD?
Your example is pretty far off. 24 bit PCM has a flat SNR all the way from DC out to 96khz. SACD has no where near that. Instead the SNR starts out comparable to 24 bit PCM and then drops off rapidly as frequency increases, somewhat similar to vinyl. The bitrate of the SACD is 1/2 as much, but its only storing a tiny fraction as much information.
If your metric is bandwidth*SNR/bitrate, then PCM is a indeed a much more efficient encoding. Every time you add a bit to your word length, you half your error energy. For 1 bit DSD, to half your error energy, you need a 4 fold increase in sample rate, which means you need exponentially more data to give a linear increase in SNR, compared to PCM where you need linearly more data for exponential increases in SNR.
Edit: At least thats my understanding.
Ok, so at what point does DVD-A overtake SACD assuming you can incrementally adjust the number of bits and sample rate in DVD-A and assuming a middle-of-the-road SACD player in terms of signal reconstruction?
Do we have any objective studies that indicate that DVD-A is audibly superior to SACD when it comes to multichannel applications?
Ok, so at what point does DVD-A overtake SACD assuming you can incrementally adjust the number of bits and sample rate in DVD-A and assuming a middle-of-the-road SACD player in terms of signal reconstruction?
Do we have any objective studies that indicate that DVD-A is audibly superior to SACD when it comes to multichannel applications?
According to this paper:
http://sjeng.org/ftp/SACD.pdf (http://sjeng.org/ftp/SACD.pdf)
Finally, consider 8-bit, four-times-oversampled PCM with
noise shaping. This is also a data rate one-half that of DSD and
double that of CD, with a sampling rate of 4 × 44,100 =
176,400 Hz. It can achieve a noise floor 120 dB below full
scale up to 20 kHz, using 96 dB of noise shaping, and a total
noise power of –19 dBFS. Its frequency response would be
flat to 80 kHz. This example is perhaps the most instructive of
the lot. For a data rate one-half that of DSD, it achieves a
comparable signal bandwidth, with a similar noise power
density up to 20 kHz, but much lower power above this
frequency, and 28 dB lower total noise power. It is fully
TPDF-dithered, and so is completely artefact free. At one-half
the data rate it outperforms DSD on every count! DSD is a
profligate wastrel of capacity.
It would seem that somewhere between CD bitrate, and twice CD bitrate DSD is overtaken by PCM. Though I cannot comment on the analysis done to conclude that.
Thanks.
Considering that SACD has only twice the bitrate as CDDA, we're actually in the ballpark.
...and my second (meat and potatoes) question?
Thanks.
Considering that SACD has only twice the bitrate as CDDA, we're actually in the ballpark.
Well, 4x the bitrate of CD anyway (705kbps vs 2.8Mbps).
...and my second (meat and potatoes) question?
Since its still up for debate if either is even better then CD on a per channel basis, I don't think theres likely to be much difference between the two. Efficiency is nice to have, but if you put the bitrate high enough, almost anything can be made to sound transparent.
Well, 4x the bitrate of CD anyway (705kbps vs 2.8Mbps).
So 2-channel SACD has a bitrate of 5.6Mbps?
...and my second (meat and potatoes) question?
Since its still up for debate if either is even better then CD on a per channel basis, I don't think theres likely to be much difference between the two. Efficiency is nice to have, but if you put the bitrate high enough, almost anything can be made to sound transparent.
I'm not sure I follow you. Do we have any objective studies that indicate that DVD-A is audibly superior to SACD when it comes to applications with more than two channels?
So 2-channel SACD has a bitrate of 5.6Mbps?
Yes.
Do we have any objective studies that indicate that DVD-A is audibly superior to SACD when it comes to applications with more than two channels?
Since I doubt such a difference exists, I cannot provide you with evidence that such a difference exists. Otherwise I would not be in doubt.
So 2-channel SACD has a bitrate of 5.6Mbps?
Yes.
Are you absolutely sure? I'm having a hard time verifying this. A follow-up question would be, how is the information for each channel split? Everything I'm reading is extremely vague.
So if you doubt that there's no audible difference in applications of more than 2 channels and you also believe SACD is an inefficient format in terms of bw and snr, where's the trade-off? Is SACD not capable of storing as much audio (number of channels * duration of each channel) as DVD-A?
SACD is also divided in 1/75 second frames of interleaved channels. So at 64×fs a frame covers 37632 DSD samples per channel with total bitrate of 5,6Mbps (when DST is not used—it is optional for 2-channel-only disks).
Hold on... Since when do we care when technology was invented? Back in the early 90s MP3 was absolutely amazing... is it still? No.
Late 90's, not early. And yes. it still.
The original question was "Why SACDs?" and I interpreted that to be "Why drop an older technology for a newer technology?" My answer is simple, in THIS day and age, CD Audio just doesn't cut it. I don't care how perfect it was back in the 70s.
It is as perfect today as it was in the 80's (not 70's.)
You don't even know why it doesn't cut it and yet you say it!!!
And yes. It does cut it.
The only reason for SACD existence is multichannel capabilities.
What problem does SACD solve for the vast majority of listeners?
Sound quality? Not likely on almost all consumer listening gear for almost all listeners (especially with loudness war, current pop mastering techniques, etc.)
Cost? Nope, more expensive.
Convenience? No - less content; less hardware selection and more copy restrictions. A lot less convenient vs. MP3, AAC, etc.
Size? No - same 12cm disc.
Availability? No - more limited distribution.
Features - some - stores images, text, multichannel, video(?), but CD can store text and the rest don't seem worth switching a format for.
I'm not convinced there is a compelling case for mass market SACD. DVD-Audio isn't really much different. Guess thats why I've never bought either one.
Cost? Nope, more expensive.
Convenience? No - less content; less hardware selection and more copy restrictions. A lot less convenient vs. MP3, AAC, etc.
Size? No - same 12cm disc.
Availability? No - more limited distribution.
These are key. If the studios released everything on microSD cards with a normal file system where everything was simply MLP compressed PCM files or something similar consumers would be all over it. Either that or go the cost route and release audio only non-DRM blu-ray titles where one disc can have the entire works of an artist for $30. Consumers would be all over that too!
have the entire works of an artist for $30
Keep DREAMING!
have the entire works of an artist for $30
Keep DREAMING!
If you look at the cost of used CDs on amazon for any band that has come out since 1989 you can already do that now. And you can do the same thing on Vinyl for any artist older than that. The music industry needs to come to terms with the true value of their music catalog. The only albums that cost more are the ones that were never popular in the first place.
Of course! Because the Beatles never really were all that popular.
Of course! Because the Beatles never really were all that popular.
You beat me to it! Another not-obscure group still at full-price, and with a large catalogue of LP-length discs, is the Rolling Stones. I remember spending a nice amt of my army-draftee pay years ago on their stuff from 1964-73.
...but you guys aren't abiding by his arbitrary rules, when it comes to the Stones and the Beatles, you have to settle for second-hand vinyl (never mind that the $30 may only cover the shipping charges).
Ok, show me where I can get the entire collection of the Dave Matthews Band or Dream Theater for only $30.
...but you guys aren't abiding by his arbitrary rules, when it comes to the Stones and the Beatles, you have to settle for second-hand vinyl (never mind that the $30 may only cover the shipping charges).
Ok, show me where I can get the entire collection of the Dave Matthews Band or Dream Theater for only $30.
From Amazon:
* Under the Table and Dreaming (1994) 2.25
* Crash (1996) 1.94
* Before These Crowded Streets (1998) 1.94
* Everyday (2001) 2.71
* Busted Stuff (2002) 4.54
* Stand Up (2005) 1.99
subtotal = 17.92
shipping = 17.88
total = 35.80
Not quite $30 but Busted Stuff has held it's value for some reason.
As for the vinyl examples, you guys would have to come with me to the swap meet every week and you have to be a lot more patient. But trust me, I've gotten most of the classics for only $1. The ones I like I'll buy on CD but it saves me a TON of money to buy them on vinyl first and give them a few spins.
You forgot Remember Two Things and the live releases which have songs not found on the studio albums.
How about Dream Theater?
Maybe SACD vs DVD-A can be interesting, after all
My two cents..
This is also a data rate one-half that of DSD and
double that of CD, with a sampling rate of 4 × 44,100 =
176,400 Hz. It can achieve a noise floor 120 dB below full
scale up to 20 kHz, using 96 dB of noise shaping, and a total
noise power of –19 dBFS.
DSD is "1bit PCM with noise shaping", isn't it? So if you say
"PCM with noise shaping is more efficient than DSD" you say "
there is a more efficient noise shaping algorithm than DSD's one". So the challenge is between noise shaping algorithm here (and I must understand them better to say anything else here)
But DSD noise shaping is
"analog": if the "better" algorithm you can use for PCM is digital, you require an higher resolution digital source to process it and downsample, don't you? How much high?
And how can I get it?
Maybe using a DSD A/D converter, with its inherent noise shaping, with actual technology can be more convenient than using a high res PCM ADC, process the digital signal with a DSP, and downsample.
This is from a production perspective (DSD vs PCM). For consumers all this debate (SACD vs DVD-A) is worthless, since mp3 is the way to go
If you have any reference to technical documentation about DSD and noise shaping please post some links, I'm really curious to read it when I will have some time.
DSD is really Pulse-Density Modulation (http://en.wikipedia.org/wiki/Pulse-density_modulation) (PDM).
So 2-channel SACD has a bitrate of 5.6Mbps?
Yes.
Are you absolutely sure? I'm having a hard time verifying this. A follow-up question would be, how is the information for each channel split? Everything I'm reading is extremely vague.
So if you doubt that there's no audible difference in applications of more than 2 channels and you also believe SACD is an inefficient format in terms of bw and snr, where's the trade-off? Is SACD not capable of storing as much audio (number of channels * duration of each channel) as DVD-A?
I think SACD is probably only 2x overkill. DVD-A is more like 100x more then is needed. That is the trade off. One is much more ridiculously over-speced then the other.
So 2-channel SACD has a bitrate of 5.6Mbps?
Yes.
Are you absolutely sure? I'm having a hard time verifying this. A follow-up question would be, how is the information for each channel split? Everything I'm reading is extremely vague.
So if you doubt that there's no audible difference in applications of more than 2 channels and you also believe SACD is an inefficient format in terms of bw and snr, where's the trade-off? Is SACD not capable of storing as much audio (number of channels * duration of each channel) as DVD-A?
I think SACD is probably only 2x overkill. DVD-A is more like 100x more then is needed. That is the trade off. One is much more ridiculously over-speced then the other.
Thanks Mike (and thanks to eevan also) for clarifying.
"Why 1-Bit Sigma-Delta Conversion is Unsuitable for High-Quality Applications":
http://sjeng.org/ftp/SACD.pdf (http://sjeng.org/ftp/SACD.pdf)
very interesting article, in short - SACD is bad and DVD-Audio (PCM output) is the right way to go for advanced resolution audio
And the test referenced in this thread (http://www.hydrogenaudio.org/forums/index.php?showtopic=57406&hl=) indicates that advanced resolution audio really doesn't provide any tangible benefit to the end user.
Do we have a comprehensive article that addresses analog reconstruction (frequency and phase response) between PCM and SACD as it's applied in practice?
Do we have a comprehensive article that addresses analog reconstruction (frequency and phase response) between PCM and SACD as it's applied in practice?
I think that this is from November 2000 Stereophile by David Rich:
Because DSD uses a high-order delta-sigma modulator (7th order–stated earlier in the text), the noise above 20kHz rises very quickly. (The higher the order, the faster the rise.) To prevent high levels of high-frequency energy from getting out of the player, an analog low-pass filter at 100kHz is required during SACD mastering. Even so, a large amount of out-of-band noise might be passed on to the power amplifier, perhaps as high as a tenth of the full power output of the system. If not rolled off by the amplifier, this may be just below the energy level to harm a tweeter. This is why SACD players are required to use a further 50kHz low-pass filter on their outputs (though this can be defeated). The need for these low-pass filters works against claims that DSD has wide bandwidth and low phase shift.
I have added the italic text
I was just curious to search some data to verify my previous post.
http://www.analog.com/en/subCat/0,2879,760...F0%255F,00.html (http://www.analog.com/en/subCat/0,2879,760%255F789%255F0%255F%255F0%255F,00.html)
http://focus.ti.com/paramsearch/docs/param...R_2000084|EQ|24 (http://focus.ti.com/paramsearch/docs/parametricsearch.tsp?family=analog&familyId=390&uiTemplateId=NODE_STRY_PGE_T&virtualTreeURL=D_PARAMETER_2000084|EQ|24)
I made this (very little) research: it seems that all high resolution analog/digital converters from Analog Devices and Texas Instruments use sigma-delta modulation to perform the conversion, and then they internally translate from sigma-delta to PCM.
I must investigate further, but I think we can't compare PCM vs DSD without accounting that modern AD converters use "DSD" natively.
DSD is not bad because of its noise shaping algorithm, but because it is a 1-bit system that has an inherent SNR of 6 dB (lots of quantization noise). In order to make something useful of this, it has to be heavily noise shaped so that this noise is pushed up to ultrasonic frequencies and a decent SNR is achieved at audible frequencies (20 Hz - 20 KHz).
20 or 24 bit PCM does not need any noise shaping to get better SNR than DSD, I mean, it has better SNR than DSD without resorting to using noise shaping. But it can be noiseshaped in the same fashion and achieven even higher SNR, but this would be absurd, because without noise shaping it is already around or over the limits of real-world electronics (~120 dB SNR).
Another problem with 1-bit systems is that they can't be properly dithered, which means that they can't be made totally distortion-free from a digital point of view, whether this is audible or not. Higher than 1-bit systems can be properly dithered so that the are totally distortion-free from a digital point of view. Only distortion at the output of these digital systems would be the caused from the analog electronics of the ADC and DAC, but not from the digital nature of the system.
Edit: AFAIk modern converters are not internally 1-bit anymore, but a few bits instead.
Edit: DSD is a pain to process. PCM is much easier and in practice everything is recorded and processed in PCM and then converted to DSD for SACD. Noise shaping of DSD is not analog, it is digital.
I must investigate further, but I think we can't compare PCM vs DSD without accounting that modern AD converters use "DSD" natively.
Those modulators are not 1-bit as DSD is. That is a huge difference.
In order to make something useful of this, it has to be heavily noise shaped so that this noise is pushed up to ultrasonic frequencies and a decent SNR is achieved at audible frequencies (20 Hz - 20 KHz).
...and it would seem as though the product has been brought to market and a second generation seems to be in the works.
Are you suggesting that it's actually broken or incapable of delivering on the published specifications?
Higher than 1-bit systems can be properly dithered so that the are totally distortion-free from a digital point of view. Only distortion at the output of these digital systems would be the caused from the analog electronics of the ADC and DAC, but not from the digital nature of the system.
So it's not like PCM formats don't have their own difficulties and shortcomings when it comes to sampling and reconstruction.
...and it would seem as though the product has been brought to market and a second generation seems to be in the works.
I have this 2003 article:
SACD II will be announced in September. That is the news reaching us here at
High Fidelity Review from a number of different sources.
High Fidelity Review has learnt that SACD II will introduce at least two
significant changes; enhanced video content and improved copy-protection
measures.
But I don't know what's going on now with SACD II.
I must investigate further, but I think we can't compare PCM vs DSD without accounting that modern AD converters use "DSD" natively.
Theres not much difference between a DSD and an oversampling PCM DAC. TI's site is a great reference. On some of their PCM and DSD DACs, the difference between the two modes is a single pair of muxes that switches the oversampling stage on or off.
I wouldn't say they use either natively. The design of each is so similar its not very meaningful to make such distinctions.
In order to make something useful of this, it has to be heavily noise shaped so that this noise is pushed up to ultrasonic frequencies and a decent SNR is achieved at audible frequencies (20 Hz - 20 KHz).
...and it would seem as though the product has been brought to market and a second generation seems to be in the works.
Are you suggesting that it's actually broken or incapable of delivering on the published specifications?
He explained how they met those specifications, and you replied asking him if they met them. Your reply doesn't really make sense.
Higher than 1-bit systems can be properly dithered so that the are totally distortion-free from a digital point of view. Only distortion at the output of these digital systems would be the caused from the analog electronics of the ADC and DAC, but not from the digital nature of the system.
So it's not like PCM formats don't have their own difficulties and shortcomings when it comes to sampling and reconstruction.
The short comings of PCM are inherent in DSD as well. The problems with DSD do not apply to PCM. This is the distinction. DSD is a failed format in the sense that it attempted to improve PCM, but actually kept all of the bad things about it while making entirely new problems (dithing, etc).
Those modulators are not 1-bit as DSD is. That is a huge difference.
They are 1-bit sigma delta.
If you look at Analog Device site, only the AD1974 uses a strange "multi bit sigma delta" that is an Analog Devices patented technology (and I don't know if it is better and why it should be)
Also I picked one data sheet from Texas Instruments:
the
device can be used to achieve 24-bit analog-to-digital
(A/D) conversion with no missing codes. Effective
resolution of 20 bits can be maintained with a digital
filter bandwidth of 1kHz at a modulator rate of 320kHz.
This probably is one of the best TI ADC. As you can see, "effective resolution" decrease with frequency, as expected (another I read was 22bit "effective" at 1 khz).
Noise shaping of DSD is not analog, it is digital.
I must check this, but I remember that the "noise shaping" of sigma-delta modulators is "performed" by the analog part of the modulator (the loop that contains the integrator). Btw "analog" or "digital" is meaningless, I would only say that sigma delta could be a more efficient (=cheap) way to do it.
However I agree that all audio is mixed and processed using PCM, so SACD need another PCM->DSD conversion. So my thoughts
- sigma delta is convenient to make high res ADC
- SACD are worthless, because you will need another PCM->DSD conversion, and as you say, this seems to be problematic.
- DVD-A are worthless too, because they aren't only over-speced for the user, but also for our actual recording equipment, since the sigma delta->PCM conversion in the ADC will retain all the sigma-delta SNR. (maybe you can record on DVD-A a pretty fully synthetic sound )
Well, things could change if class D amps will become popular (so you will need PCM->DSD conversion anyway), if we start to process audio using sigma-delta DSP, or using better ADC that can really fill a DVD-A.
Anyway all this is stupid: mp3 (or flac) rulez!
You're right, I haven't look at the links. That's something I vaguely recall from ADC lecture when I was at the university. I can't find the notes, but I'm pretty sure the professor talked about multibit sigma delta modulators.
- DVD-A are worthless too, because they aren't only over-speced for the user, but also for our actual recording equipment, since the sigma delta->PCM conversion in the ADC will retain all the sigma-delta SNR. (maybe you can record on DVD-A a pretty fully synthetic sound )
The noise level at the output of a SACD rises quickly above 20 KHz. If I remember well, at 20 KHz the noise is already higher that in good old CD. In a good 24 bit 96 KHz or 192 KHz converter noise does not rise with frequency, it keeps a good SNR over the whole bandwidth, as should be.
Sigma-delta PCM converters use a very high sample rate and internally process a vast amount of data, but only the useful part of that data goes to the output. DSD keeps all that data, including the useless high frequency noise, and as sigma-delta systems they are very inferior to internal delta-sigma converters of PCM systems, I mean, they use a much lower sampling rate and nº of bits. That's why PCM sigma-delta converters have much better performance than SACD and work as they should.
- DVD-A are worthless too, because they aren't only over-speced for the user, but also for our actual recording equipment, since the sigma delta->PCM conversion in the ADC will retain all the sigma-delta SNR. (maybe you can record on DVD-A a pretty fully synthetic sound )
This is a really, really strange conclusion given that modern audio ADCs achieve the highest SNR of basically any type of ADC in production, and more or less the best possible performance physically possible without cryogenic cooling.
I wouldn't say they use either natively. The design of each is so similar its not very meaningful to make such distinctions.
If I have well understood, the design is so similar because both them use sigma-delta, so both have the same limits.
The short comings of PCM are inherent in DSD as well. The problems with DSD do not apply to PCM. This is the distinction.
If you use sigma-delta modulators to make ADC, all the problems with DSD will apply also to PCM.
DSD is a failed format in the sense that it attempted to improve PCM, but actually kept all of the bad things about it while making entirely new problems (dithing, etc).
Of course I agree it is a "failed" format. You can't store the same data of a PCM with "less space", unless you accept some compromise ...or simply you can use Flac .
Also DSD can be fully represented as 1 bit PCM with noise shaping. It is the "noise shaping" the compromise. DSD is nothing but a noise shaping technique.
Sigma-delta PCM converters use a very high sample rate and internally process a vast amount of data, but only the useful part of that data goes to the output. DSD keeps all that data, including the useless high frequency noise
Even PCM from sigma-delta will keep all the high-frequency noise, unless you filter it. But if you filter it, you will loose some of high frequency signal.
This is a really, really strange conclusion given that modern audio ADCs achieve the highest SNR of basically any type of ADC in production, and more or less the best possible performance physically possible without cryogenic cooling.
Wow! (at every frequency?) Just a curiosity: can we make full use of DVD-A without using cryogenic cooling?
(edit: sorry I miss a thing: thermal noise gives us a bottom limit. But which is the upper one? We can have more than xxxdb of dynamics if I set the lower reference at 1Volt)
I'm sorry maybe I'm making a lot of confusion in this thread because I'm speaking about DSD without accounting SACD specs, and because of my english. Anyway I hope my perspective to account actual recording technologies is giving some fun to SACD vs DVD-A fight, and giving some information even to casual reader.
I wouldn't say they use either natively. The design of each is so similar its not very meaningful to make such distinctions.
If I have well understood, the design is so similar because both them use sigma-delta, so both have the same limits.
This isn't true. Using sigma delta puts a lower bound on the problem, but not an upper bound. I can certainly have all the problems of a sigma delta ADC, and still have plenty more unrelated ones too.
And indeed, this is what happens with DSD.
Sigma-delta PCM converters use a very high sample rate and internally process a vast amount of data, but only the useful part of that data goes to the output. DSD keeps all that data, including the useless high frequency noise
Even PCM from sigma-delta will keep all the high-frequency noise, unless you filter it. But if you filter it, you will loose some of high frequency signal.
I already explained this:
If your metric is bandwidth*SNR/bitrate, then PCM is a indeed a much more efficient encoding. Every time you add a bit to your word length, you half your error energy. For 1 bit DSD, to half your error energy, you need a 4 fold increase in sample rate, which means you need exponentially more data to give a linear increase in SNR, compared to PCM where you need linearly more data for exponential increases in SNR.
http://www.hydrogenaudio.org/forums/index....7491&st=25# (http://www.hydrogenaudio.org/forums/index.php?showtopic=57491&st=25#)
The efficiency is much higher in the PCM case as you can trivially verify. Why are you trying to complicate such a simple thing with irrelevant details about filtering? Just compute the bits needed to double the SNR for both encodings at a 20kHz bandwidth and you'll see why none of this matters.
Just a curiosity: can we make full use of DVD-A without using cryogenic cooling?
(edit: sorry I miss a thing: thermal noise gives us a bottom limit. But which is the upper one? We can have more than xxxdb of dynamics if I set the lower reference at 1Volt)
You can't go much higher then 1 V anyway, and since we're on a log scale, it doesn't really matter. You could maybe get logic working at 5v if you spent a whole lot of money. Thats not even a 10dB gain. And it'd be cheaper to buy chillers for your gear . . .
You could maybe get logic working at 5v
I see... the upper bound!
Every time you add a bit to your word length, you half your error energy.
I'm starting to remember something... If you increase the bandwidth of a PCM signal, you can reduce the quantization noise in audio band, because you spread the same noise power across all frequencies.
I remember that sigma-delta is a much more efficient way to trade more bandwidth for less noise.
(I was lucky, all these formulas are on wikipedia http://en.wikipedia.org/wiki/Sigma-delta_m...heory_formulas) (http://en.wikipedia.org/wiki/Sigma-delta_modulation#Quantization_theory_formulas))
Of course this means absolutely nothing, because you may want to choose a different metric to measure "efficiency". Maybe SNR(audioband)/space(bytes)? Who is so brave to make this calculus? ^^''.
Also maybe you can find a better digital noise shaping filter to achieve better performance with PCM, if you have a better PCM source to process. The paper someone linked seems to say this.
Anyway 1 bit "plain" PCM needs much more bandwidth to achieve the same SNR in the audio range than 1 bit DSD (="1 bit PCM using DSD noise shaping"... yea, it is obvious)
So this could be relevant if each "bit" you add to PCM "costs" more than bandwidth, for example for making ADCs, where complexity grows exponentially with bit-rate. (and you don't have a better digital source to process...)
Again, this is all related to ADCs. If you have a better digital source to downsample, and a better noise shaping filter, why the hell should you go to DSD??
Why are you trying to complicate such a simple thing with irrelevant details about filtering?
Because I was focusing in my mind the advantages of sigma-delta (when bit depth is not an option)
Every time you add a bit to your word length, you half your error energy.
I'm starting to remember something... If you increase the bandwidth of a PCM signal, you can reduce the quantization noise in audio band, because you spread the same noise power across all frequencies.
I remember that sigma-delta is a much more efficient way to trade more bandwidth for less noise.
(I was lucky, all these formulas are on wikipedia http://en.wikipedia.org/wiki/Sigma-delta_m...heory_formulas) (http://en.wikipedia.org/wiki/Sigma-delta_modulation#Quantization_theory_formulas))
Of course this means absolutely nothing, because you may want to choose a different metric to measure "efficiency". Maybe SNR(audioband)/space(bytes)? Who is so brave to make this calculus? ^^''.
I can't parse any of this. It would help if you didn't write in the form of a stream of consciousness narrative. Punctuation is also recommended.
Again, this is all related to ADCs. If you have a better digital source to downsample, and a better noise shaping filter, why the hell should you go to DSD??
I don't think this has anything to do with ADCs or noise shaping. Its a simple matter of minimizing RMS error / bit. You're overcomplicating a simple idea by confusing everything you read with some nonsense about ADCs. Theres nothing mentioned here that has even the slightest bit to do with ADCs aside from your original observation that most DSD and PCM ADCs and DACs are nearly identical.
Why are you trying to complicate such a simple thing with irrelevant details about filtering?
Because I was focusing in my mind the advantages of sigma-delta (when bit depth is not an option)
The advantage of sigma delta is that it allows for very high bit rate ADCs at reasonable cost. However, this has nothing to do with anything you've mentioned.
Hi-res PCM (DVD-A) is much more efficient and better from an objective quality point of view.
From the document that krabapple referenced:
Practice so far shows that DSD is at least as sonically transparent as 192kHz/24 bit and better than 96kHz/24bit. However, one channel of DSD takes up only 2.8Mbit/s, whereas one channel of 192kHz/24bit takes up 4.6Mbit/s.
Yes, and that is one line I wanted to know the most about, but Mssrs. Putzys et al. didn't expand on that.
No published ABX data that I can find. What 'practice' are they referring to? IT'S THE VERY CRUX OF THE ISSUE and yet, again, frustratingly, no listening data is presented. It isn't a technical argument. So referencing it is an us another appeal to audio authority and anecdote, and nothing more.
"Why 1-Bit Sigma-Delta Conversion is Unsuitable for High-Quality Applications":
http://sjeng.org/ftp/SACD.pdf (http://sjeng.org/ftp/SACD.pdf)
very interesting article, in short - SACD is bad and DVD-Audio (PCM output) is the right way to go for advanced resolution audio
Careful. SACD technology changed soon after that 2001 paper --DSD Wide was introduced -- and it has been argued that its objections no longer hold.
You forgot Remember Two Things and the live releases which have songs not found on the studio albums.
How about Dream Theater?
You're right, I guess they had an independent release before those others. It's another $4 on to the total. That's a lot of value right there for $40.
With Dream Theater I can't even come close. I ran into something similar six months ago when I bought all the Pixies albums that I didn't have. They were all at least $6. Probably wasn't as many Dream Theater albums pressed as Dave Matthews by far.
Maybe $50 for such a one disc entire catalog disc would be more in line. It would probably depend a lot on how prolific the band's catalog was. You can already pick up things like the The Doors complete collection for $80. That's six complete albums and a rarities disc. Mastering all of that to one disc would save the record companies a ton in manufactuing and distobution costs.
Hi,
It has been a while since I posted here and that has to do with me. So, don't worry.
The question: "Why SACD?" is for me very simple to answer:
* it is multichannel (5.1 format which can be seen as an optimum*)
* it gets the attention an audiophile would like, that is no loudness war or something like that
That's it. Of coarse the technique is quite different and one could talk for hours and hours about potential benefits and other stuff which occurs in the very low level amplitude domain but in practise this is not relevant. The dynamic range of a human being is something like 80 dB or somewhat more and according to this paper in the September issue of the AES (Audibility of a CD-Standard A/D/A Loop Inserted into High-Resolution Audio Playback), it is very questionnable wether the increased bandwidth is necessary at all. I quote:
"Conventional wisdom asserts that the wider bandwidth and dynamic range of SACD and DVD-A make them of audibly higher quality than the CD format. A carefully controlled double-blind test with many experienced listeners showed no ability to hear any differences between formats. High-resolution audio discs were still judged to be of superior quality because sound engineers have more freedom to make them that way. There is no evidence that perceived quality has anything to do with additional resolution or bandwidth."
One could debate for hours and days about this but the bottom line is that it is apperantly very hard to tell the difference. Otherwise the outcome would be different.
Regards,
Jacco
*) T. Muraoka en T. Nakazato, "Examination of Multichannel Sound-Field Recomposition Utilizing Frequency-Dependant Interaural Cross Correlation (FIACC)", J. Audio Eng. Soc., Vol. 55 No 4, pp. 236 - 256 (April 2007).
I can't parse any of this. It would help if you didn't write in the form of a stream of consciousness narrative. Punctuation is also recommended.
I'm sorry Mike I try to do my best to write English.
So 2-channel SACD has a bitrate of 5.6Mbps?
Yes.
Are you absolutely sure?
It's the rate of the
uncompressed stream. But an SAVD stores a losslessly compressed version of it (DST = direct stream transfer) which reduces the rate by about 50%.
A follow-up question would be, how is the information for each channel split? Everything I'm reading is extremely vague.
Uncompressed DSD is usually interleaved at a byte level. 8 bits for channel1, 8 bits for channel2, 8 bits for channel1, ... (for stereo). The proposed standard file format for DSD streams (DSDIFF) can be downloaded for free (sorry no reference at hand). DSDIFF files also support the DST compression sheme. Last time I checked the MPEG4 reference source code package included a DST->DSD decoder in its lossless subdirectory. You might want to check it out.
Grimmaudio AD1 manual (http://www.grimmaudio.com/Manual%20AD1.pdf)>> Practice so far shows that DSD is at least as sonically transparent as 192kHz/24 bit and better than 96kHz/24bit.
Huh? "better than 96kHz/24bits"? Did I miss something?
Grimmaudio AD1 manual (http://www.grimmaudio.com/Manual%20AD1.pdf)>> However, one channel of DSD takes up only 2.8Mbit/s, whereas one channel of 192kHz/24bit takes up 4.6Mbit/s.
So? 384Hz/32bit has an even higher rate. You need only 8 bits/sample at a rate of 192 samples/sec (1.5MBit/s) to outperform DSD already (!)
Careful. SACD technology changed soon after that 2001 paper --DSD Wide was introduced -- and it has been argued that its objections no longer hold.
Still, SACDs store DSD only.
Cheers!
SG
It's the rate of the uncompressed stream. But an SAVD stores a losslessly compressed version of it (DST = direct stream transfer) which reduces the rate by about 50%.
Multichannel SACDs employ DST for both 5.1 and stereo tracks, but it's optional for discs with 2-channel track only.
Uncompressed DSD is usually interleaved at a byte level. 8 bits for channel1, 8 bits for channel2, 8 bits for channel1, ... (for stereo). The proposed standard file format for DSD streams (DSDIFF) can be downloaded for free (sorry no reference at hand). DSDIFF files also support the DST compression sheme. Last time I checked the MPEG4 reference source code package included a DST->DSD decoder in its lossless subdirectory. You might want to check it out.
Just to help, here is the link for the DSDIFF spec: http://www.sonicstudio.com/pdf/dsd/DSDIFF_1.5_Spec.pdf (http://www.sonicstudio.com/pdf/dsd/DSDIFF_1.5_Spec.pdf)
and usage recomendations: http://www.sonicstudio.com/pdf/dsd/DSDIFF_...mendedUsage.pdf (http://www.sonicstudio.com/pdf/dsd/DSDIFF_1.5_RecommendedUsage.pdf)
Careful. SACD technology changed soon after that 2001 paper --DSD Wide was introduced -- and it has been argued that its objections no longer hold.
Still, SACDs store DSD only.
You're right. DSD Wide is used in processing stage to make DSD manipulation easier. It is downconverted to regular 1-bit DSD for SACD mastering.
As for the original question: why SACDs? My answer to that would be: why not?
They and the equipment you need are more expensive, even to produce, and they are harder to rip than CD, with all their DRM.
This is all true, but when viewing SACD as an alternative format, and not as a primary format, these issues are less critical. I feel the same way about DVD-Audio. Both have failed to achieve wide-market appeal, but both are reasonably 'good' formats. Nine times out of ten, I'd prefer a DVD-Audio release over a SACD release, but I see little inherently wrong with SACD. The players are expensive, absolutely, but this is intended to be an 'audiophile'-grade format, and as such, the cost of entry is a bit prohibitive. I'm also not truly sold on 1-bit DSD/PDM, at least not from a theoretical perspective (rhetorical: it can't capture certain waveforms as accurately as 24-bit/192 kHz PCM -- but does it sound better or worse with real program material?).
We might be getting hit in the wallet a bit, but an SACD-capable system is really quite an optional endeavor. Odds are that, if you know what it's all about, you can likely afford both the hardware and 'software', and even if you don't, you're not really missing a whole hell of a lot. So, hey, alternative formats not impacting the primary formats -- why not?
Careful. SACD technology changed soon after that 2001 paper --DSD Wide was introduced -- and it has been argued that its objections no longer hold.
Still, SACDs store DSD only.
You're right. DSD Wide is used in processing stage to make DSD manipulation easier. It is downconverted to regular 1-bit DSD for SACD mastering.
Well allrighty then
http://en.wikipedia.org/wiki/Direct_Stream_Digital (http://en.wikipedia.org/wiki/Direct_Stream_Digital)
There has been much controversy between proponents of DSD and PCM over which encoding system is superior. Professors Stanley Lipshitz and John Vanderkooy from the University of Waterloo, in Audio Engineering Society Convention Paper 5395 (2001), stated that 1-bit converters (as employed by DSD) are unsuitable for high-end applications due to their high distortion. Even 8-bit, four-times-oversampled PCM with noise shaping, proper dithering and half data rate of DSD has better noise floor and frequency response. However, in 2002, Philips published a convention paper arguing against this in Convention Paper 5616. Lipshitz and Vanderkooy's paper has been criticized in detail by Professor James Angus at an Audio Engineering Society presentation Convention Paper 5619. Lipshitz and Vanderkooy responded in Convention Paper 5620.
I see little inherently wrong with SACD. The players are expensive, absolutely,
Not at all absolutely. There are SACD players on the market for <$200 (e.g. from Oppo).