Where is the magic in a SHM disk?

I'm hypothesizing that ripping and burning will be the same mastering. The same way copying digital photos from one type of media to another does not affect the composition, quality, or contents of the photos themselves.

Bingo. This is the information that I'm after. Which CDs, specifically, are you referring to? If you can provide catalog numbers or bar codes, I'll do my best to purchase them for myself. For those CDs, if they do sound different, I would form this hypothesis:

Aluminum CD -> EAC will be equal to
Aluminum CD -> EAC -> CD-R -> EAC

and also

SHM CD -> EAC will be equal to
SHM CD -> EAC -> CD-R -> EAC

However, I would bet that

SHM CD -> EAC will not be equal to Aluminum CD -> EAC again, if they do sound different.

If you're willing to run that experiment for the same byte for byte albums that you own on both standard CD and SHM-CD I believe the board would be very interested in the results.

 

Thanks for weighing in Mr. Gerber.

 

This is absolutely true.

I don't agree with Holy Diver as to why SHM CDs sound different because I think it is something to do with the material and way it reacts to each individual player. It's not about "errors".

But there is a way to determine the difference:

1. Take one SHM CD and one CD: Test in EAC and make sure they are 100% identical and cancel out.

2. Run your analog outputs to a PC. Play and record a song from the standard CD to your PC.

3. Do the exact same thing with the SHM CD, using the same player, everything the same!

4. Compare the frequencies of the tracks as they were recorded to your PC.

As I say, I think the material reacts differently to different players, so this wouldn't necessarily prove that a difference would be heard on every single CD player, but I think that a small difference would show up in the frequency analysis of the two discs as recorded using the exact same chain of playback.

For the record, I don't really believe in sonic differences in digitally identical discs. I was amazed that there was a difference with SHM and I chalk it up to some type of reaction the material causes on the laser.

I'm also with Holy Diver in that I think two discs that are identical where one is SHM and one is not either have almost no difference worth being concerned about or, if anything, the SHM is usually worse.

 

Gladly.

Analogies are helpful:

If you glue sawdust to the outside of a paperback book, it may affect how much you enjoy reading the book (<--> ANALOG), but it won't change the words that are inside the book (<--> DIGITAL).

 

I think my experiment (#240) is just as scientific as anything else offered here.
The only variable in the equation is how well the pits on an SHM or conventional CD cause the "toggle buffer register" (or whatever its called) on the input to the D/A to toggle. With a mint CD or mint SHM, and a fully operationally compliant player, its almost always going to be 100%. Once that hurdle is cleared, everything else is identical.
So therefore you get the same sound out of your speakers. Like I did with my Joe Jackson SHMCD and CD.

 

No, they are getting a more accurate sonic representation of what exactly is on that CD. Just because you don't hear it doesn't mean it is non-existent. It's like trying to go 100 MPH on a mini-bike and calling it an equal to a Harley Davidson if it were fortunate enough to reach that speed.

It's your money, but I'll put my Japan 1st pressing of Harvest and After The Gold Rush up against these SHM CDs any day. There's not one SHM CD I've heard [yet] that will be able to touch the sound quality on these.

To all of you who seem to enjoy these modern sounding remasters thank you for continuing to buy them so the good sounding older CD pressings are readily available to those of us that prefer them. Without the proper sound staging, mainly depth, I do not enjoy listening to these modern paintings being passed off as the end all and be all of sonics.

Just some old guys insane view who owns a $3000 boat anchor called an SCD-1.

 

Ha! I just ordered the SHM version of "After the Gold Rush" to use for my experiment. It was $40 (US), but for the sake of science, it's a small price to pay - especially since I don't already own the album. Thanks for the recommendation, bluesfan.

When it arrives, I'll gladly report my findings back to the group - whether they're what I expect or not. It might be a couple of weeks.

Still, Holy Diver, if you could let us know which albums you own bit-for-bit identical copies of on "standard" CD and SHM-CD, please post the details here. I'd be willing to drop a few bucks on getting my own copies to analyze. Again, in the name of science.

 

Except there's no definition for what that (in your words) "sonic representation" should be.

Digital audio standards say that if you have a particular stream of 0s and 1s (represented by pits and lands on a CD), you'll get (for example) a 5kHz sine wave at a particular volume. However, there are no standards that say things will sound (for example) more or less "veiled" depending on how the pits and lands are recorded or what material is used to press the discs.

The more a player produces differences between different pressings of the same material, the *less* accurate it is. The "accurate sonic representation" is stored in the digital data. If two CDs have the same digital data but sound different (gold vs. aluminum, SHM vs. Blu-Spec, 1x burn vs. 48x burn, etc), there's a problem with the playback device, period.

That isn't to say such things can't or won't happen, but it is wrong to suggest that is good or correct behavior.

 

There are ones and zeros on the CD. Any $5 cd-rom drive can read them. There is only one "sonic representation" of those ones and zeros, and that is the decoded PCM data, 16 bit, 44,100 Hz waveform. This can by easily proved by reading the CD multiple times using different drives and comparing the checksums of the PCM data. Those checksums will always be the same, the waveform is always precisely the same. Anything else that happens to the sound after that is irrelevant to this specific discussion.

 

Burning to CD-R you introduce new variables. People on this forum have reported that their CD-R copies sounded better than the CD. This is attributed to less jitter in the burning process than in manufacturing. And not all CD-Rs sound the same as test of Hi-Fi magazines have shown. So you have to compare the SHM-CD to a normal CD with the same mastering as has been said before.

 

But you don't take jitter into account. That's why the sound can be improved with a master clock.

Even the ripping to a hard-disc isn't that easy. That's why Exact Audio Copy was developed.

 

It's easier than you think, at least today. EAC is essentially "belt and suspenders". Assuming a disc that isn't poorly pressed or very scratched, most half decent drives today should rip with complete accuracy even in burst mode. Try it...

 

The problem is these CDs are not great masterings to begin with. I would hate to see you spend the money on these even to prove a point. I bought what I have when I did not know any better before coming to this forum. I will tell you what I have, but please don't spend money to prove something. It is not worth it. I already made the mistake in buying these, but you don't have to. It is your dime, though.

Yngwie J. Malmsteen's Rising Force

UICY-93352 - Regular CD

UICY-93547 - SHM

Both have 2007 mastering on them, and are Mini LP CDs. They may be OOP, as well.

By the way, the best mastering of this album is the good old US original non-remastered release you can get at Best Buy for $10. Just to let you know.

 

PLL jitter was all but eliminated with Sonys, Philips (and everybody elses) 1992 range of players.

 

And what if the diagnostic program isn't as accurate as both the player and the ears listening? Think of it more like that annoying problem/noise your car has every so often. You take it to the dealer to find out and fix it and S.O.B. nothing shows up on the diagnostics and does not repeat with even multiple visits even though sure as rain every so often it happens.

Since when is sound quality not relevant for discussion on an audiophile music forum?

 

I dunno Luke, I'm glad my player can tell me if a CD sounds dimensional/believable and life-like or like listening to an oil painting. You can call it faulty all you want.

 

That's actually a terrible analogy.

The point is, if your CD sounds "dimensional/believable and life-like or like listening to an oil painting", that is stored in the digital data. That is the sound of the mastering. If you have two CDs with the same data, and one *doesn't* sound like that, there's a problem with your player. Why do I say that? Because if you extract the data to your hard drive, the data from both CDs will sound the same. In your terms, "dimensional/believable and life-like or like listening to an oil painting".

To put it another way, if you have two digitally identical CDs, and one sounds the way you described it above, and the other *doesn't* sound that way, your CD player isn't playing the other CD properly. There's nothing in the CD specification that would tell a player to play the two discs differently. The (apparent) fact that they don't sound the same is a flaw in the playback mechanism.

 

Well, CD jitter is pretty old news by this point, but the big manufacturers can only go so far before diminishing returns and marketplace realities come to play. What may be "all but eliminated' to you may still be way too much to others. As to what Barry mentioned earlier, Sony even changed their disc mastering methods at one point in the mid 90s to use a large RAM buffer after so many artists and producers and engineers were complaining that their finished CDs didn't sound as good as the original even though they passed a data comparison. Stereophile made measurements of pit jitter and showed spectrums in an article they ran. At one point the CD specification was updated to include a pit jitter limit, and there is test equipment to measure it. Not that it has much to do with the original SHM discussion, but this thread seemed to lose focus awhile ago

 

We are in agreement.....Fully!

 

With the same mastering on a conventional CD and SHM-CD, if PLL jitter happens with one format on a particular piece of equipment, it will happen with the other format on the same piece of equipment, because as I said earlier on, the only variable in the CD vs SHM debate is the laser read which with mint CDs/SHMCDs and fully functoning equipment will be perfect in all cases. (So thats not even a variable for mint CDs)
This is my last post on this particular subject. You can have the last word if you want.

 

Sorry, I shouldn't have mentioned master clocks. It was just a clumsy way to say that jitter exists and can have an influence on sound quality. So it's not just about 1s and 0s that stay the same all the time.

 

If I extract these two different sounding CDs with the same digitally identical mastering to my hard drive which one will these extracted files actually sound like? Will it be the life-like or the oil painting? What if I burn back to CD-R and play on the same faulty player? Does everyone who is hearing the same mastering sound different own "faulty" CD players?

 

If CD's with digitally identical mastering sound different on your CD player...how exactly do you know when you've got the very best sounding one available? No matter what you have in your possession, there may be another one floating around out there that might sound better. Even if it comes from the same pressing plant, same mastering, same catalog number, etc. There will always be that doubt.

 

I'll definitely look for them as time permits. In the meantime, could you extract the data from each and report the results back to the group?

 

It will be whatever the original mastering sounded like, before being pressed onto CD. Barry has indicated this repeatedly. The extractions of both discs will sound the same.

Depends how you burn it.

In the sense that they are not correctly producing the sound as it was mastered and can be heard upon extraction, yes.

To repeat: there is no specification anywhere for CD players that would make digitally identical discs sound different. That (apparently) some/many/all (depending on who you ask) players exhibit this behavior is a flaw, and is not something that is in any way advantageous.