Help, I'm ready to buy into either SACD or DVD-A (1 Viewer)

[KeithH]

Lee said:

I think we should stop arguing this as we have reached an impasse.

No offense to you or John intended, but this impasse was reached a long time ago.

 

[John Kotches]

Lee,
Let's go back and look at Ian's words, shall we?

DSD stage for output. (I don't know if there may be SACD decoders available which do no post-processing whatsoever, but if you have a chip which is even capable of bass management, dollars to donuts the bass management runs on PCM).

From this, I gather him saying that if you do any processing -- in this context that means bass management and time alignment you are no longer left with straight DSD.
The statements do not preclude a straight DSD out of the uncompressed DST stream, provided you accept the signal as is. In which case, break out 5 full range speakers spaced equidistant from the primary listening position for best results.
Perhaps you should ask Ian where he gets his information... I'm certain statements aren't lacking foundation or he wouldn't make them.
With respect to JAs writings on DSD, it's clear he's read the literature.
Regards,

 

[Lee Scoggins]

No offense to you or John intended, but this impasse was reached a long time ago.

Agreed!

 

[Lee Scoggins]

I just heard from Sony. They are using a DSD-based DSP chip in their SACD players.
So that appears to be pure DSD for me!

 

[John Kotches]

Lee,

It means that it takes DSD input and has DSD output. That doesn't say anything about the data within the chip. Sony's mixing station takes DSD in and out, and does the conversion internally.

Custom Silicon is ruthlessly efficient at these types of tasks.

Regards,

 

[John Kotches]

Lee,

Yesterday, I said this:

Why can't you measure the amplitude of the waveform with changes in 8-bit, or "wide DSD" as Sony would call it and also have 8-bit PCM conversion which uses height?

Are they not two different things? In wide DSD, it is the change of the wave, not the absolute value, therefore is Delta-Sigma Modulated...

Once you start using multi-bit values you are sampling (or quantizing or quantifying whichever you choose to call it) the amplitude of the change. Once you stop dealing with up or down and start quantifying by asking "how much did it change" (multi-bit) you have just used PCM to sample the amplitude of the change. PCM measures amplitude (height), in this case, it's the amplitude of the change, and not the original wave.

Regards,

 

[JaleelK]

From this, I gather him saying that if you do any processing -- in this context that means bass management and time alignment you are no longer left with straight DSD.
The statements do not preclude a straight DSD out of the uncompressed DST stream, provided you accept the signal as is. In which case, break out 5 full range speakers spaced equidistant from the primary listening position for best results.

This have been a very spirited debate, I have read every post in this thread, it has been very interesting and informative. I'm not an engineer and really don't understand all of the technical words being used by both sides of the debate. Both sides of this debate seems well informed, even above the typical layperson or average audio ethusiast who just might be considering purchasing a DVD-A or SACD player, reading this thread, with all the technical stuff could a little daunting for such person. Nonetheless its good reading for anyone interested in the technical side of these two formats, pro and con.
Having read this thread, most of the post coming from Lee and John, I must ask myself who's right and who's wrong? Someone must is right and someone must be is wrong, that has to be the case in a debate. Who really have the facts regarding what's being debated here? If you are layperson how can you determine who's right? Which person debating is more credible here? Who have backed their argument of with evidence and proven facts?
As someone who's not an engineer and doesn't have technical background, I take a more legal like approach, in the manner of trial lawyer, to determine who has proven there argument and has given real evidence in their case, in other words, to determine who's right and who's wrong. Where does the evidence seem to point to, in who's favor does evidence leans to? Let deal with to very sticking issues that I felt was hotly debated in this thread.
1) On the issue of Ian's post quoted in John's posted above, did Ian make an argument that preclude a straight DSD out of the uncompressed DST stream? I would have to agree with John, no he did not, no where in any of the foregoing post in this thread did Ian say that DSD out of the straight DST stream wasn't possible nor did he infer it.
2) On the question SACD being pure market hype Ian said " SACD as it is now is pure hype, because the theory of DSD is trumpeted over and over, but in actual recordings and actual players, any potential advantages are eliminated by PCM processing stages (while leaving the disadvantages). Lee said in response " This is simply not true. There are many pure DSD recordings out there which clearly highlight the benefits of Super Audio. The problem with PCM conversions has largely been solved by new mastering workstations put out by Sony and EMM Labs. " John rebuttal to Lee ,in part thereof, " We don't know whether the newest Sony mixing stations are using an intermediate steps that involve PCM, as it's a black box. "
From this discussion you can place somethings in evidence to ascertain facts. Is it pure hype? From Sony's own website they make thew following claim " DSD's direct signal path also has a dramatic effect on the purity and "feel" of the music. Even the most advanced PCM record/playback systems utilized in conventional CDs require decimation and interpolation filters that can cause problems, including requantization noise, ripple and ringing. These degradations can smear musical overtones, muddy the soundstage and compromise overall transparency. In a radically simpler approach, DSD processing, as used in Super Audio CD, eliminates these problems by dispensing with these extra filters. This direct DSD recording process is one of the leading advantages of Super Audio CD".
In Lee's very own statements, he seems to concede that PCM conversion was a problem, that is now being resolved with the introduction of the new Sony workstations. Even by Lee's own consession, Sony is not living up to "DSD's direct signal path" evidenced by the PCM conversion problem, so there is definately proof of marketing hype by Sony. John made mention that we don't know whether the newest Sony mixing stations are using an intermediate steps that involve PCM, this statement were not rebutted by Lee. Even the website cited by Lee on SACD say's the following "
DSD in Production.
The DSD pulse train can be downconverted to conventional PCM digital audio. But in the long run, the full benefits can best be retained by an all-DSD production chain. Both Sony and Philips have begun serious work on that chain. Prototype DSD-capable recording systems already exist. In addition, Sonic Solutions is developing a DSD-compatible version of Sonic’s well-known SonicStudio™ line of digital audio workstations."
Even by Sony and Phillips own admissions those workstations mentioned by Lee seem to be a future goal of Sony and Phillips.
Lee also made the statement" The Sony multi-channel players like the XA777 do not use any DSD-PCM conversion to retrieve multi-channel sound. The DSD process is totally complete in these DSD players.
How can this be true when Sony and Phillips have yet to resolve the PCM conversion problem? If the XA777 do not use any DSD-PCM conversion, then the technology already exist and shouldn't be a future goal.
Sony's claim of " The high-density layer can also contain a Direct Stream Digital six-channel recording of the same piece of music. Each of the six channels Can be recorded separately with full 100 kHz frequency response and 120 dB dynamic range. As a result, the six-channel sound image has unparalleled resolution and transparency. " have yet to proven in the real world and can be deemed as marketing hype. In one of John post on this he showed a list of SACD players that failed to fufill SACD's aforementioned claims: I'll show you the exact pages that demonstrate SACDs inability to deliver the claimed 120dB dynamic range:
Pioneer DV-AX10 Measurements -100dB @ 20kHz *Converts DSD to PCM for D/A Conversion
Sony XA-777ES -90dB @ 20kHz
Sony SCD-C555ES -75dB @20kHz
Classe` Omega SACD player -90dB@20kHz
Philips SACD-1000p -90dB@20kHz
These numbers were not rebutted with any test measurement or other scientific data which again establishes the evidence in favor of John and Ian on the issue of marketing hype.

 

[John Kotches]

Jaleel,

Lee and I do have spirited debate, but here's one thing that I don't think you're interpreting correctly.

Lee also made the statement" The Sony multi-channel players like the XA777 do not use any DSD-PCM conversion to retrieve multi-channel sound. The DSD process is totally complete in these DSD players.

How can this be true when Sony and Phillips have yet to resolve the PCM conversion problem? If the XA777 do not use any DSD-PCM conversion, then the technology already exist and shouldn't be a future goal.

There are multiple phases here, and I'm glossing over them leaving out tons of details. Steps where PCM comes into play have a * by them

1) Initial capture of recording. DSD.
*2) Mixing of recording. Wide DSD (Sony's term) 8bit @2.8mHz, Philips' verision 32-bit@352kHz.
*3) Post processing, for example building a 5.1 channel mix (which requires post processing) Wide DSD for Sony, 32/352 for Philips.

4) Delivery to Consumer back to DSD again.

This ends the "recording studio" side of the signal chain.

This part is done in the player itself.
5) Decompress / seperate out 6 channel info.
* 6) If bass management and time alignment are required there's a PCM step in there. If not, this is bypassed.
7) D/A is done for analog output.

So, you have to look at where these steps are. Lee is correct so long as there is no Bass Management and Time Alignment, when speaking of the operations inside the player.

Regards,

 

[Lee Scoggins]

Well I didn't expect to have to spend so much time on the Forum today, but the last two posts have several bits of misinformation. Starting with Jaleel...
First, the problem with Ian's original post (as I have now said twice) is that he implied there was no pure DSD in the player itself. That remains simply wrong and I will explain in further detail below. He goes on to talk about the post-processing, that is an entirely different story.

Lee is correct so long as there is no Bass Management and Time Alignment, when speaking of the operations inside the player.

Actually I am correct on Bass Management and Time Alignment as well, based on my research. My understanding from several high level discussions is that these things (BM, TA) are handled by DSD chips in the players.
Even more exciting has been development of a true DSD interface module, MAC-DSD, which allows 24 bi-directional channels of 64fs DSD, with the "clock" not buried in the digital signal which greatly eliminate a lot of jitter problems.
So you have DSD fully developed at present for a completely edit-able data stream. "Pure DSD" does exist and if you listen to these recordings, your ears will be amazed. The DSD technology continues to develop apace.
As reported in this month's Stereophile, even Lipshitz and Vanderkooy's death match theory battle with Jim Angus and Derk Reefman has quieted down with Lipshitz and Vanderkooy accepting the fact that dithering the digital signal leads to idle tones being unmeasurable at -180db.
That reminds me...two things about Jaleel's measurments above. First, Sony has reported higher numbers and Two, and its a big one, 90db of dynamic range is still awesome! More importantly is what does the dynamic range contain in between as we say in the business...
Do the cymbals sound real in DSD? Yes
Does the attack of the piano notes and the latter decay sound natural? Yes
Is the tonality of the instruments natural? Yes
But you decided friends of the HTF.
I do agree with Jaleel on one thing. I think this discussion has been healthy since John and I are passionate about our different beliefs. It draws out technical aspects that highlight the importance of different things and show the complexity of high resolution formats. It also shows that digital audio is a constantly moving target just like PC performance.

 

[JaleelK]

So, you have to look at where these steps are. Lee is correct so long as there is no Bass Management and Time Alignment, when speaking of the operations inside the player

Do you mean that Lee is correct about PCM, as there is no BM or TA? I maybe a bit off in my analysis, however let try to clarify somehting happening here.

If so, I don't think he actually agreed to that, his argument seems to be, even with post processing(bass management, time alignment)included, with Sony multichannel players like XA777, that its all done in the DSD domain. In the foregoing post in this thread here are some of the things that were said, especially as it relates to the actual players.

1)Ian said " in actual recordings AND ACTUAL PLAYERS". I would love if you would find for me a DSD DSP which does not internally do DSD-PCM then PCM-DSD for effects processing.

Note how Ian puts in capital letters AND ACTUAL PLAYERS. Trying to place special emphasis on them. Ian is putting forth a challange to Lee, Lee's responds and rebutt Ian.

2)Lee said " Again, not true. The Sony multi-channel players like the XA777 do not use any DSD-PCM conversion to retrieve multi-channel sound. The DSD process is totally complete in these DSD players."

Unless Lee is being evasive to the question from Ian, I don't think he is, Lee is in disagreement with DSD-PCM conversion in the players even for post processing.

3)Further along in the thread John said" With players, so long as we're talking no signal processing, ie Bass Management and Time Alignment, it's already been said that it is not necessary to perform a PCM transformation. All that's done on a 5.1 stream without BM and TA is a DST decompression, and a passthru to the appropriate DAC(s)."

Again, Lee is saying, according to some of the statements he made that I read, I get the impression that he's in disagreement here, as he cites that the XA777 needs not use any DSD-PCM transformation.

As a consumer, If I go to my nearest hi-fi shop and purchase a Sony SACD XA777 player, hook it to my systems, my satellite sub system and tell it perform bass managemnt,sending bass in below a certain frequency point in all channels to the sub what is happening here is some PCM involvement taking place when I do this ? Isn't this really what it all comes down to ?

BTW Lee, I get mad at Sony due to the lack good bass management in the players and no power on/off button on the remote, I'm still mad at them for that. I like SACD, more for its multichannel capabilties as opposed to the claims of sonic purity and superior to CD sound.

 

[Lee Scoggins]

As a consumer, If I go to my nearest hi-fi shop and purchase a Sony SACD XA777 player, hook it to my systems, my satellite sub system and tell it perform bass managemnt,sending bass in below a certain frequency point in all channels to the sub what is happening here is some PCM involvement taking place when I do this ? Isn't this really what it all comes down to ?

Maybe you should be concerned that the BM and TA is done properly, but I would worry most about the quality of the multi-channel sound as delivered by the DSD decoder. That is going to be 90+% of the sound and realism thereof.

 

[John Kotches]

Lee,

With respect to:

As reported in this month's Stereophile, even Lipshitz and Vanderkooy's death match theory battle with Jim Angus and Derk Reefman has quieted down with Lipshitz and Vanderkooy accepting the fact that dithering the digital signal leads to idle tones being unmeasurable at -180db.

Is this the same Stereophile that reported Meridian skipped out on the Munich AES with no explanation, and that Meridian was developing an SACD player? Both have been denied by Bob Stuart as being grossly incorrect.

Forgive my skepticism, but they have earned this through their printing of unsubstantiated and unverified rumors.

Further, the Angus/Reefman paper was presented at the latest AES in Munich, V&L always respond one to two AES' following, after they have studied the paper presented.

Not having an immediate reply is standard.

Regards,

 

[Neil R]

Great info, it's nice to read a civilized debate. Thank you.

I bought a Toshiba 4700 for it's DVD-A playback. I was using it in my dedicated 2 channel system. I was very disapointed in it's redbook playback and thought the DVD-A 24/96 version of "Two Against Nature" was not that much different than the redbook. I tried the unit in my basement HT rig in 2 channel and multi and again was pretty disapointed. I do not care for the multi channel version at all. I ended up returning it for a sony 775 SACD player and found it to be far superior in 2 channel redbook performance and was wowed by the "We Are In Love" SACD by HC jr.

In my short time of using both formats, SACD sounds much better to my ears in my system.

John, I have emailed you in the past and am in Elgin also. You are welcome to come by for a listen. I did sell my maggies though for Triangles.
NR

 

[Lee Scoggins]

Is this the same Stereophile that reported Meridian skipped out on the Munich AES with no explanation, and that Meridian was developing an SACD player? Both have been denied by Bob Stuart as being grossly incorrect.

I heard about this long before Stereophile reported it as my friends were present in Germany and said the same thing. Again, a major "weakness in SACD" as reported by the DVDA camp shot to pieces. Check the proceedings it is in the AES papers.
John,
I have decided that it is no longer worth my time to debate these technical issues if you are going to respond like this and insult my intelligence. I went to a lot of trouble and time to respond so the whole of the HTF could learn something about the DSD and PCM technologies.
In the future, get a new sparring partner. I'm out.

 

[Stephen Houdek]

Isn't this quite similar to the VHS vs. Beta days? We all know who won that one.........

It really doesn't matter which format is best. "People" aren't going to run out and buy a Sony player just so they can get SACD. Neither format will "take off" until they are mainstream and the prices for the discs fall into CD territory. People are going to buy a DVD player that also happens to play DVD-A and will end up buying DVD-A's to play on it if they have the desire and budget. Economics will decide, not technical superiority.

 

[Lee Scoggins]

Economics will decide, not technical superiority.

It may actually be both: economics on the consumer side and technical superiority (or ease of use in archiving) on the professional side.

The consumer alone will not decide the success of the format. It is entirely possible DSD could survive as a niche format or as a professional archiving tool.

I think if the average consumer is educated and marketed to properly, they will learn to appreciate high rez. Even on a crappy midfi Bose system, high rez is loads better...

 

[Lee Scoggins]

I have decided to stay in for the learning experience of digging deep into the technologies.

I am currently talking to some very big name friends in the business including Barry Wolifson (engineer of Chesky) and Mark Levinson about some of the technology specifics. I have also tried to reach David Kawakami of the Sony Super Audio Project as well.

My goals are to:

1. Gain in-depth knowledge of DSD editing chips and workstations.
2. Explain to the membership DSD mixing is done with no loss of information.
3. Report any important views on future Super Audio improvements in the pipeline, such as pre-distortion filters recently tested.
4. Elevate our collective knowledge of the importance of various areas of the recording chain and its impact on the final CD/SACD/DVDA.

For ease of use, I will likely start another thread devoted just to these technical matters and do my best to keep the DVDA versus SACD opinions to a minimum. In other words, just report what is going on in the technology at the current time.

If I can persuade my friends to register and participate for the benefit of the HTF, I will surely do so.

Best regards,

 

[Stephen Houdek]

Lee, that would be great.....I look forward to your information and the debates I'm sure it will create. This is interesting stuff, even though, at times, things get a bit "hot"!

It would do us all some good if we were more civil to each other at times......Even in the heat of a passionate debate.

 

[John Kotches]

Sorry for my absence, the past few days -- life has been busy.

Lee,

I said my example was a simplification to illustrate a point, and I'm sorry you took in a manner that wasn't intended.

The point being illustrated is that there are two divergent values at a given point in time, but only one of the values can be encoded with a 1-bit system.

So how does it get encoded? You have to go multi-bit. Determine which channel is going to have a greater net effect at that point in time, and record the value for the result as the delta at that point in time.

I could see this as becoming very bandwidth intensive as you add more and more channels that are under consideration at a point in time.

Regards,

 

[Lee Scoggins]

John,

I will respond to this in a new post when I have finished my research.

Lee