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CD and SACD formats questions - Page 2

post #16 of 40
Quote:
Originally Posted by plonter View Post
Thanks for the replies guys. i wouldn't mind trying some SACD records,but i won't be able to use my dac because i can't get a digital output from an SACD player. any solution for this?
No. You wouldn't be able to use your DAC anyway as your DAC works on PCM digital audio rather than the DSD technology employed on SACD, these two different digital audio technologies have quite a lot in common but are incompatible. DSD works on the principle of a 1bit (yes, one bit!) datastream with a sampling rate of 2.83mFS/s (yes, 2.83 million samples per second!).

G
post #17 of 40
Quote:
Originally Posted by gregorio View Post
Why? I've got plenty of professional, personal and anecdotal experience to back up my assertion, plus plenty of scientific evidence. What more do I need?
Obviously you don't need more. But that's you.


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I would say your assumption goes too far. You've provided your own personal experience but this is in conflict with scientific measurement and DBT evidence. Differences can be easily measured between the formats (SACD, CD and Hi-rez) but these differences fall well below the threshold of human hearing.
Apparently they don't. Of course with your personal background you're bound to dismiss my personal experience, but to me it's as valid as yours is to yourself. The pretended official hearing threshold is fine for establishing ideologic bias, but fails to represent reality. A DSD signal shows quite some measuring differences to a redbook CD signal – even more so than the output signals of modern amps which according to the official hearing threshold all sound the same, but refuse to do so.


Quote:
As I said in my first post in this thread, SACD usually sounds better than red-book because of slight (or sometimes not so slight) differences in the master. For this reason SACD sometimes represents the best quality listening experience available to the consumer at this point in time. This is sometimes also true of Hi-Rez, although at any normal listening level Hi-Rez should be indistinguishable from CD...
I'm going to interrupt your litany... I haven't even pretended that SACD sounds better in every respect, just that it sounds different. That's my point. I have provided some evidence how I've gained this conviction, but I see that you don't like to give this approach of mine any credit and prefer to stick with your own conviction that it's all in the mastering.
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post #18 of 40
Quote:
Originally Posted by JaZZ View Post
I'm going to interrupt your litany... I haven't even pretended that SACD sounds better in every respect, just that it sounds different. That's my point. I have provided some evidence how I've gained this conviction, but I see that you don't like to give this approach of mine any credit and prefer to stick with your own conviction that it's all in the mastering.
If your conviction could be professionally verified or replicated under test conditions then I would be prepared to question the scientific facts. But the consensus of professionals, independent controlled testing and the science are all in agreement. Weighing your perception of what you're hearing against my personal experience, the consensus of professionals, independent tests and science is for me, not a difficult choice.

Quote:
Originally Posted by JaZZ View Post
A DSD signal shows quite some measuring differences to a redbook CD signal:
They display massive differences because they are different technologies. It's not difficult to measure the differences when one is 1bit 2.83mHz and the other is 16bit 44.1kHz. If there weren't differences there would be a serious problem. The differences between the outputs of the DACs however are the differences between the outputs of the DACs, not necessarily differences between the formats.

Quote:
Originally Posted by JaZZ View Post
.. even more so than the output signals of modern amps which according to the official hearing threshold all sound the same, but refuse to do so. :
I've seen you post this argument before but frequency responses quoted by amps are often close to or within the capabilities of human hearing. Whereas the specifications of red-book CD are beyond human capabilities, let alone Hi-Rez. In fact not only is CD beyond human capabilities, it's even well beyond the capability of any DAC on the market to reproduce.

G
post #19 of 40
Quote:
Originally Posted by gregorio View Post
... Whereas the specifications of red-book CD are beyond human capabilities, let alone Hi-Rez. In fact not only is CD beyond human capabilities, it's even well beyond the capability of any DAC on the market to reproduce.

G
While agreeing in large part with there being fairly good evidence that RedBook is good enough in practical music delivery I think you've gone beyond the evidence with these last few claims

“Coding High Quality Digital Audio”:

http://www.meridian-audio.com/w_paper/Coding2.PDF

The paper is very technical (by head-fi standards at least, it is a “popularization” of a JAES convention paper) Stuart summarizes some of “conventional” audio engineering/psychoacoustic understanding of human perception limitations and their relation to reproduced audio – people might want to jump to the figures/graphs at the end of the paper and then search back into the text for the explanatory context

I think the takeaway from the paper is that RedBook is practically good enough but there are a few edges/corners of the best estimates of human aural perception that CD doesn't quite cover - checkout figs 19 and 20 - clearly the "acute hearing threshold" curve of fig 20 is going to cross the noise shaped dither 16 bit lines of fig 19


as for commercial DAC performance - you are aware that ESS Saber equipped DACs are shipping?
HeadRoom Ultra Desktop DAC @ HeadRoom
it looks to me like the raw DAC noise floor of the paralleled implementations are comfortably below even optimal noise shaped dithered 44.1/16 bit dynamic range
http://www.headphone.com/pdfs/sabrewp.pdf
post #20 of 40
Quote:
Originally Posted by gregorio View Post
If your conviction could be professionally verified or replicated under test conditions then I would be prepared to question the scientific facts. But the consensus of professionals, independent controlled testing and the science are all in agreement. Weighing your perception of what you're hearing against my personal experience, the consensus of professionals, independent tests and science is for me, not a difficult choice.
Yes, I understand your position under these circumstances.


Quote:
They display massive differences because they are different technologies. It's not difficult to measure the differences when one is 1bit 2.83mHz and the other is 16bit 44.1kHz. If there weren't differences there would be a serious problem. The differences between the outputs of the DACs however are the differences between the outputs of the DACs, not necessarily differences between the formats.
Well, I guess the differing format should reflect itself in the output signal, no? An upper limit of 22 kHz against one of 48 kHz isn't nothing and leaves its traces in the signal shape. Furthermore, DSD comes with a bunch of ultrasonic noise (→ noise shaping) that's often not or not completely suppressed by any low-pass filtering, sometimes deliberately so. Add to this that the (equivalent of) barely 8 bit of dynamic range that DSD originally has at around 20 kHz and below is likely to cause some sonic artifacts not curable by mere noise shaping.


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I've seen you post this argument before but frequency responses quoted by amps are often close to or within the capabilities of human hearing.
And which FR deviations exactly do you have in mind then? –0.2 dB at the extremes (20 Hz–20 kHz) is the maximum deviation from a straight line with 95% of modern amps. I agree with you that that isn't audible if you agree with me. Apart from that, such minor FR deviations don't account for the perceived sonic characteristics, such as transparency, clarity, dryness, liquidness, smoothness, graininess, threedimensionality... I often edit some recordings for a perceivedly more even sonic balance (with 1 dB as the finest step available). It doesn't fundamentally change the above-mentioned amp characteristics.

To me the greatest disadvantage of the SACD format is that it isn't editable.
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post #21 of 40
Quote:
Originally Posted by plonter View Post
Hi all. Is the difference between sacd and regular cd really noticeable? or subtle...? I want to know if its worth to get myself an sacd player.
Both: noticeable and subtle. These days the benefit from an SACD player is doubtful. The format is about to die, or at least there aren't many new SACDs released, plus the musical variety is (and always was) limited compared to CDs. You have to be seriously interested in highest-quality music reproduction or multichannel playback for taking the plunge. And you better like classical and Jazz.


Quote:
Do all SACD recordings sound good, or maybe part of them are not so big improvements over the normal cd recording..?
The latter is the case. I'd say, at best 50% really provide the advantage of the format.
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post #22 of 40
Go with SACD if you want surround, if stereo only CD is fine.

Your DAC need to support DSD and HDMI if you want to get DSD out of your SACD player and the SACD player need to have the HDMI out too.
post #23 of 40
i won't get into supporting a person in this thread, but i have spend quite a bit of time with very high end redbook and sacd systems and honestly, don't hear the difference. some people do and some dont. i say that it is placebo or not, but a lot of my mates listened to a track or an album and assuming it was sacd, said it sounded so much better, but in the end it was redbook.

i fell for the same thing too several years ago. it may entirely be possible that our ears are not up to the stats that our brain is ready to convince them with.
post #24 of 40
I may conceed that with the same, high-quality recording/mastering, the same, high-quality player (read: four-figures & up) with equally high-level DSD & PCM sections, the sonic advantage may be minimized, if not leveled.

The problem is that everything starts with the source material/recording & the people engineering it. The aforementioned recording rarely exists. My experience has shown that DSD recordings/masters are more often done at the highest level, perhaps with the expectation of the engineers that the music will be played back on very good or better systems, for discerning listeners. In contrast, my experience with Redbook has shown that that the recording/mastering is more typically done with the mindset that it will be played back on low-fi systems to undiscerning listeners.

Given that, it stands to reason that a greater percentage of DSD (and hi-rez DVD-A) discs will have better sounding recordings on them (including the PCM layer if available), than the percentage of strictly Redbook discs. This has made my universal player, in a headphone-only system, quite the worthwhile expenditure, for now & at least the near future.

Cheers, y'all.

post #25 of 40
Quote:
Originally Posted by jcx View Post
While agreeing in large part with there being fairly good evidence that RedBook is good enough in practical music delivery I think you've gone beyond the evidence with these last few claims

“Coding High Quality Digital Audio”:

http://www.meridian-audio.com/w_paper/Coding2.PDF
That's a good and accurate paper ... or at least it was. My guess is that it was written at least a dozen years ago, possibly even 15 years ago. Since then, noise-shaped dither tools have advanced a fair bit. 16bit (with modern noise-shaped dither) is capable of reproducing a dynamic range of 150dB in the critical hearing band and up to 139dB in a much wider band.

The Sabre Audio DAC has a dynamic range of 130dB, which is very impressive but still ten times less than the theoretical upper limit of 16bit (150dB). If you think that the electrons colliding inside a 1.8k resistor are going to produce noise down at the -138dB level, then you'll appreciate why I said that electronics are not (ever) going to be able to reproduce the theoretical limit of red-book. Furthermore, this is all academic anyway, I've never heard (or heard of) a recording with a dynamic range larger than about 65dB and most are less than 35dB. If the full dynamic range of CD were actually used and could be reproduced, it would cause pretty much instantaneous deafness anyway. On a very dynamic recording, at least 5 (and as many as 12) of the least significant bits (LSBs) on a CD only contain noise, so all that 24bit gives you is an additional 8 LSBs of noise, plus less storage space.

So with all this in mind, how on earth could the consumer benefit from 24bit?

Quote:
Originally Posted by JaZZ View Post
Well, I guess the differing format should reflect itself in the output signal, no?
As I've mentioned, even red-book goes beyond human hearing and the capabilities of electronics. So the electronics in the analogue output stage of the DAC (even the finest DAC) are going to have more effect on the signal than the actual digital format.

Quote:
Originally Posted by JaZZ View Post
An upper limit of 22 kHz against one of 48 kHz isn't nothing and leaves its traces in the signal shape. Furthermore, DSD comes with a bunch of ultrasonic noise (→ noise shaping) that's often not or not completely suppressed by any low-pass filtering, sometimes deliberately so. Add to this that the (equivalent of) barely 8 bit of dynamic range that DSD originally has at around 20 kHz and below is likely to cause some sonic artifacts not curable by mere noise shaping.
20kHz is about the absolute limit of human hearing. Also, 20kHz is the limit of the vast majority of studio mics. And lastly, producers and engineers do not want too much content above 20kHz in the recording because they can't hear it and therefore can't mix it.

Noise-shaping in DSD systems is a real can of worms and is one of the technical disadvantages of SACD vs CD.

Quote:
Originally Posted by JaZZ View Post
And which FR deviations exactly do you have in mind then? –0.2 dB at the extremes (20 Hz–20 kHz) is the maximum deviation from a straight line with 95% of modern amps... Apart from that, such minor FR deviations don't account for the perceived sonic characteristics, such as transparency, clarity, dryness, liquidness, smoothness, graininess, threedimensionality... I often edit some recordings for a perceivedly more even sonic balance (with 1 dB as the finest step available). It doesn't fundamentally change the above-mentioned amp characteristics.
Theoretically, 0.2dB is just within the capabilities of some highly trained ears and therefore potentially audible to some. Whereas 150dB dynamic range is about ten times louder than the pain threshold and 22kHz is also beyond the hearing of human beings.

Actually, FR and also noise, could potentially account for pretty much all the characteristics you mentioned, depending on how the amp interacts with the colouration of the speakers or cans. Of course, crosstalk, phase issues and a number of other measurable factors are on occasion also just within hearing capabilities and could also potentially change the perception of some of the characteristics you mentioned. It's very unlikely that anyone could hear any of these limitations but in combination and also considering how the amp interacts with other components, the figures are in the ball park of what could be audible to some people. Not so with red-book.

BTW, professional audio software (such as ProTools for example) usually allows for adjusting volume in 0.1dB steps.

G
post #26 of 40
Quote:
Originally Posted by gregorio View Post
As I've mentioned, even red-book goes beyond human hearing...
Yes, but we were talking of the signal shape (not its psychoacoustic interpretation) – which varies considerably between redbook CD and SACD.


Quote:
...and the capabilities of electronics.
I can't follow you here. Redbook CD is ...Hz to 22 kHz, electronics can have much higher bandwidth and much lower harmonic distortion. In terms of S/N ratio it's about equal (since both use similar electronics components). The theoretical S/N ratio of the format may slightly exceed that of current electronics, though, but who cares.


Quote:
So the electronics in the analogue output stage of the DAC (even the finest DAC) are going to have more effect on the signal than the actual digital format.
Definitely not. See above! The SACD signal may have significant frequency content above 22 kHz and moreover suffers less from bandwidth-limitation artifacts (filter resonances, phase distortion) from both ADC and DAC.


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20 kHz is about the absolute limit of human hearing. Also, 20 kHz is the limit of the vast majority of studio mics. And lastly, producers and engineers do not want too much content above 20 kHz in the recording because they can't hear it and therefore can't mix it.
I suppose you're talking of your own practice. In fact for hi-rez recordings the recording engineers take care for high-bandwidth microphones, otherwise the exercise would be futile.


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Noise-shaping in DSD systems is a real can of worms and is one of the technical disadvantages of SACD vs CD.
I agree. And it may be audible. There's even one electrostatic amp I can't use with SACDs (Stax SRM-Xh) because of the ultrasonic noise causing distortion.


Quote:
Theoretically, 0.2 dB is just within the capabilities of some highly trained ears and therefore potentially audible to some.
Perhaps a loudness difference of 0.2 dB is audible (to some). But it's unlikely that a 0.2 dB drop-off at 20 kHz is audible (making for about –0.12 dB at 15 kHz).


Quote:
Actually, FR and also noise, could potentially account for pretty much all the characteristics you mentioned...
Good try. But noise is definitely inaudible in my setup, apart from the noise on the recordings (which isn't an issue in the real-world amounts and wouldn't account for sound-quality issues). And frequency response... No. Very unlikely. Unfortunately Jan Meier doesn't publish the FR specs for his amps, but I guess frequency extension is similar to HeadRoom's products: Micro Amp ($333) and Desktop Ultra Amp ($1700) are both specified with 10 Hz–50 kHz –0.3 dB and 0.002% THD. Nevertheless, my four Cordas sound substantially different. Again: I haven't heard two different amps sound the same so far.


Quote:
BTW, professional audio software (such as ProTools for example) usually allows for adjusting volume in 0.1dB steps.
Yes, and sometimes I would like to have finer steps. But in the end I can cope with the 1 dB steps. I just wanted to demonstrate that an alteration of the sonic balance doesn't change the general sonic difference between the amps and the individual characteristics.

With your 0.1 dB steps you could try if you can detect a 0.2 dB drop-off (and if, how it affects the sound)!
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post #27 of 40
Quote:
Originally Posted by JaZZ View Post
Yes, but we were talking of the signal shape (not its psychoacoustic interpretation) – which varies considerably between redbook CD and SACD.
I'm not sure what you mean. If you mean the output signal then I've already explained that there are going to be significant measurement (not audible) differences between the output stages.


Quote:
Originally Posted by JaZZ View Post
I can't follow you here. Redbook CD is ...Hz to 22 kHz, electronics can have much higher bandwidth and much lower harmonic distortion. In terms of S/N ratio it's about equal (since both use similar electronics components). The theoretical S/N ratio of the format may slightly exceed that of current electronics, though, but who cares.
Electronics can have a much higher frequency range than red-book but not lower harmonic distortion, which as far as digital audio theory is concerned should be zero.

Quote:
Originally Posted by JaZZ View Post
I suppose you're talking of your own practise. In fact for hi-rez recordings the recording engineers take care for high-bandwidth microphones, otherwise the exercise would be futile.
I'm talking about standard practise, not specifically my own. The most common mics used for hi-rez recordings by far are a range of dynamic mics (always lower than 20kHz) and large diameter condenser mics such as U87s and C414s, again not higher than 20kHz!! Sounds like you are starting to get it, hi-rez is indeed "futile", my point exactly!!

There are a few mics which have higher FR bandwidths. These are sometimes used for orchestras in concert halls, very rarely (if ever) in studios.

Quote:
Originally Posted by JaZZ View Post
Perhaps a loudness difference of 0.2 dB is audible (to some). But it's unlikely that a 0.2 dB drop-off at 20 kHz is audible (making for about –0.12 dB at 15 kHz).
0.12dB @ 15kHz is very large compared to the differences people believe they can hear with cables for example. I can in fact hear a 0.2dB change on certain material and at certain frequencies. Though not @ 15kHz.

Quote:
Originally Posted by JaZZ View Post
Good try. But noise is definitely inaudible in my setup, apart from the noise on the recordings (which isn't an issue in the real-world amounts and wouldn't account for sound-quality issues).
Answer me this then: If noise is already "definitely inaudible" in your setup, what possible benefit do you expect to get from a noise floor which is another 48dB (200+ times) lower? BTW, a 48dB lower noise floor is the definitive and only advantage of 24bit over 16bit. So, you now seem to be agreeing with me and arguing against hi-rez digital audio!!

Quote:
Originally Posted by JaZZ View Post
Yes, and sometimes I would like to have finer steps. But in the end I can cope with the 1 dB steps. I just wanted to demonstrate that an alteration of the sonic balance doesn't change the general sonic difference between the amps and the individual characteristics.
I believe it can, though it may not be noticed by many. People believe they hear differences in cables but those differences are in the order of hundredths or thousandths of a dB! So 1dB should be a massive difference for a cable believer!!

G
post #28 of 40
Quote:
Originally Posted by gregorio View Post
Prices are rising because fewer recordings are being released in SACD format.
Your response to Uncle Erik's remark on rising prices of SACDs on ebay is incorrect, imo. What Uncle Erik was referring to, I believe, is the rising prices of certain used pop/rock SACD titles. These are often considered "out of print" and represent the best digital version ever released, or featured a multi-channel mix that's unique to the SACD version.

As for fewer titles being released on SACD....according to sa-cd.net, the number of new SACD titles added to that site was essentially the same for both 2008 and 2009, through the month of May for each respective year. This is actually quite a feat given the depressed economy and the lack of public awareness for SACD. Therefore, get ready to celebrate SACD's 10th anniversary this coming September as the total number of releases go past 6,000.
post #29 of 40
Quote:
Originally Posted by gregorio View Post
I'm not sure what you mean. If you mean the output signal then I've already explained that there are going to be significant measurement (not audible) differences between the output stages.
You may not remember, but that was your statement to which I responded:
Quote:
The differences between the outputs of the DACs however are the differences between the outputs of the DACs, not necessarily differences between the formats.
The higher bandwidth is definitely a difference caused by the format, not the DAC. (The same applies to bit depth, which doesn't reflect itself that clearly in the analogue signal, though.)


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Electronics can have a much higher frequency range than red-book...
That was my point.


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...but not lower harmonic distortion, which as far as digital audio theory is concerned should be zero.
You're correct. No format distorts. But in the real world the format causes higher distortion within the DACs and players than in amps and other electronics. And that's most likely a consequence of the relatively narrow frequency «headroom» of redbook CD in view of the relevant frequency bandwidth (→ antialiasing filtering).


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I'm talking about standard practise, not specifically my own. The most common mics used for hi-rez recordings by far are a range of dynamic mics (always lower than 20kHz) and large diameter condenser mics such as U87s and C414s, again not higher than 20kHz!!
So why is it that the (acoustic!) hi-rez recordings I have checked via Wavelab have considerable ultrasonic content? And it's not tape noise. In short: I don't believe you. There's just very few info on the SACD booklets. I only figured out that Opus3 used AKG C24 (FR only displayed up to 20 kHz, but doesn't end there), moreover I found a Schoeps Colette system (goes up to 45 or 50 kHz) with a Telarc recording.


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Sounds like you are starting to get it, hi-rez is indeed "futile", my point exactly!!
Not too much ingratiation, please!


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There are a few mics which have higher FR bandwidths. These are sometimes used for orchestras in concert halls, very rarely (if ever) in studios.
There we have it! I think I already showed you the Sennheiser MKH 8000 series which goes up to 100 kHz (60 kHz without any drop-off) half a year ago. I believe most of my classical SACDs are concert-hall recordings.


Quote:
0.12dB @ 15kHz is very large compared to the differences people believe they can hear with cables for example. I can in fact hear a 0.2dB change on certain material and at certain frequencies. Though not @ 15kHz.
So we agree it's not the frequency response!


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Answer me this then: If noise is already "definitely inaudible" in your setup, what possible benefit do you expect to get from a noise floor which is another 48dB (200+ times) lower? BTW, a 48dB lower noise floor is the definitive and only advantage of 24bit over 16bit. So, you now seem to be agreeing with me and arguing against hi-rez digital audio!!
I'm not worried about some low-level noise, so well-made dither would possibly do it for me. But I still favor high sampling rates. On the other hand, I can also live with the CD format, and this since quite a while. Ironically at the latest since I have the UDP-1, a universal player that can also play the hi-rez formats. The early-generation CD players sounded really «technical», though.


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People believe they hear differences in cables but those differences are in the order of hundredths or thousandths of a dB! So 1dB should be a massive difference for a cable believer.
It's not «massive» but a 1 dB treble increase or decrease is clearly audible and in 90% of the cases where altering the sonic balance is necessary the maximum I do. And note that I don't hear dBs, neither in cables nor in amps. I understand that you can't imagine any different criterion in this context, but these sonic differences and characteristics can't be expressed in terms like «brighter» and «darker», standing for corresponding shifts of sonic balance expressible in dBs.
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post #30 of 40
Normally I don't do this but...

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