[Larry]

Apart from the black disc idea, a lot of the info in that document is IMO, false.

I believe in the information on what he observed.

Audio an Data are read/interpreted differently. They are however not stored differently. They are both stored as binary digital. A HDD has no "timing" when it comes to its use, unlike an audio CD. A HDD has no "clock".

Audio and data are stored the same way on harddiscs but differently on CDs at logical levels, which makes the audio CDs and data CDs perform differently when errors occur. The difference is not only in interpretation but also in representation. However, both audio and data on CDs are read indifferently at physical level.

The chances of a CD-ROM misreading a bit are so slim, that it essentially never happens. Take a look at some cd-roms error rates...

The chances are pretty high on some CDROM drives, which demostrates in music data reading more easily. For computer data, it happends but the misreading may be corrected behind the scene so the users may not be aware.

Cd-rom error rates you mentioned may be something to do with computer data CDs, not audio CDs, I guess. If you give specific information on what error rates this refers to, I may explain what it really means. It could refer to laser pick up errors, overall errors before correction or overall errors after correction for computer data etc.

Anyway, no matter how low the error rates are, there are error rates. If you actually check your old CDROM drives, you may be surprised by how high the error rates may be, much higher than it was supposed to be.

You could maybe convince me that copies sound different from the original..but not for some of the reasons he mentioned.

Agree.

[Felipe]

Hi

Larry :

I agree with most of what you wrote, but i didnt find any comments on what you really think of the article.
I know you tried some CD-Readers and Writers, but what about the results? Because to Audio guys like us, who cares if it sounds ilogical if it sounds good?

So...did you burned some Black CD's ? Do they sound better ?
Because i can understand that the Black CD's sound better than the other types - Silver,Gold,Platinum,etc - but BETTER THAN THE ORIGINAL ???

How ?? As you said...if there is an error....there is an error !

[Tyson]

I can't comment on the sound yet, no time to do A-B comparisons, but I WILL say that the copies I burn to black CDR's definitely track better and also read the menu and "lock" in the signal faster.  That alone makes it worthwhile to purchase them, IMO.

[Larry]

Thank you Felipe - this is a question got to be asked - why a copy on black CD could be better than the original?

I agree with most of what you wrote, but i didnt find any comments on what you really think of the article.

I think the article reports his observations on the various CD media, which is interesting and useful. I basically listen to his experience seriously. As what he described, I think most of his findings could be repeated by other people. I am open to that if some of his findings can not be repeated on some poeple's system, as we are talking about very subtle differences here and some factors in play are not well known and the effects of combinations of hardware and software on individual systems are not investigated.

I do not agree with some of his explanations to what he observed, however this does not disprove his findings.

I know you tried some CD-Readers and Writers, but what about the results? Because to Audio guys like us, who cares if it sounds ilogical if it sounds good?

I experimented with CD drives to confirm that errors do occur while  reading on CD drives and  various CD drives do read CDs with different accuracy. That was when I heard that some people could hear differences between a copy and an original. At that time, what I wanted to know was if there could be any errors in reading CDs. If yes, the difference in sound could be originated from this, otherwise it must be from somewhere else.

I did not personally compare a copy with an orignal. What I did was to look into some facts that could support the difference in sound. And I did find it and it comfirms that data read from CDs are not indentical so that the differences in sound are possible.

So...did you burned some Black CD's ? Do they sound better ?
Because i can understand that the Black CD's sound better than the other types - Silver,Gold,Platinum,etc - but BETTER THAN THE ORIGINAL ???

I did not burn any black CDs yet so that I can not offer you my personal observations on this. However, if we accept that people do find the black CDs sound better, I can share with you what I think could make that difference.

1) Black CDs are late development with higher specifications which must be suitable for higher speed applications (32x speeds or more) so that black dyes and reflective backing are invented for better laser pick up accuracy than silver, gold etc.

2) The normal music CD drive is developed first and its speed now is called single speed. CDROM drives are improved based on music CD techniques and can work at much higher speeds than music CD drives. The multiple in computer CDROM speed specifications is relative to the music CD drive speed. eg. 30x speed CDROM means it works at the 30 times faster speed than music CD drives. So CDROM must have much better specifications on optical, mechanical and electronic accurrancy. So for some CDs with marginal marks, music CD drives may fail to pick them up correctly but CDROMs can. In this case, when you use computer CD drives to read it correctly and burn it clearly on a new CD so that the music CD drives could read it with better accurancy than the original with not-quite-clear marks. In addition, the CDROM drive should have better error handling capability than the CD drive in consumer CD players. Look how much more the circuitry attached to CDROM drives than a music CD drives.)

3) The normal CDs are pressed with aluminum reflective backing, which is considered not as good as gold reflective backing in terms of mechincal deformation, temperature, and optical reflection etc. So the normal aluminum  CDs could result in more reading errors than CD-RWs, say black CDs. Furthermore, pressing CDs with a mold is like printing, which could result in more errors than burning a CD bit by bit with a burner, which is designed with high accurancy for computer data storage that requires practically error-free. (The errors contained in pressed CDs are very much depend on the accurancy of mold. That's why some people said they could tell if the CD is pressed at a later stage in production, when the mold has been worn. Also Japan and Germany are well kown for their precision manufactures so that Japanese and German pressed CDs could contain less errors.)

4) If we accept that the original aluminum pressed CDs may contain more errors. Then how could the copied one contain less errors?

First, as said, the computer CD reader could read music CD with better accurancy than consumer music CD players. Second, while copying from CD to harddisc, the computer CDROM drive read the data on music CDs as data so that it could read the data multiple times if the drive detect possible errors. The repeated reading will improve the accurancy, which is normal for computer CDROM or harddiscs while music CD players are not capable doing so as music CD players have to work real time with music that does not allow it going back to read it again. This could explain why copying to harddisc first would result better sound while directly coping from reader to writer did not as the reader in this case has to work realtime at writer's speed so that reader cannot repeat reading when errors are detected. Third, the reduced errors in CDROM reading then may just within the errors correction capability so that the remaining errors are mostly corrected before they are burnt to a new CD. So, the burnt CD may therefore contains much less errors than the original.  The newly burnt black CD with cleerer marks and better reflective backing than the origanl aluminum pressed CD further assists the less performing consumer CD player to read the copied CD with much less errors than the original.

Hence the copied sounds better than original.

Is this logical?

There could be other possibilities. Please add them so that we could understand this phenomena better.

To be sure, all these have to be tested with properly designed lab experiments, but, for understandable reasons, we have to stop here.

How ?? As you said...if there is an error....there is an error !

Yes. If the errors are beyond error correction limit, errors will remain as errors and cause music distortion. It the errors are within the error correction limit, they can be cleaned. As explained above, if the errors in the original can be corrected with best effort while copying,  the copied CD could contains less errors so that it may sound better.

[Larry]

but I WILL say that the copies I burn to black CDR's definitely track better and also read the menu and "lock" in the signal faster.  

This may demonstrate that the CD players read black CDR with better accurancy.

At the initial stage, CD players need to look for a special mark pattern, called synchronisation code, to be able to track the CD tracks. If the CD players fail to find it with the first try, they will keep looking. If the black CDR could be read with less errors, the CD player may find it with the first few tries so that they appear working faster.

[Felipe]

...... Third, the reduced errors in CDROM reading then may just within the errors correction capability so that the remaining errors are mostly corrected before they are burnt to a new CD. So, the burnt CD may therefore contains much less errors than the original.  

Hence the copied sounds better than original.
Is this logical?

Thank you for your reply, its very usefull.

Now,  what you are saying is that when we are copying the CD in a CDROM drive to a hard disk, we are correcting the errors that are possible to correct ? Always ? Or must we use a special software like the one mentioned above ?
Do the CDROM drives correct the errors even when simply copying the .WAV to hard disk ?


Thanks for your post.
Felipe

[Phat Phreddy]

Great thread.  As some of you may know I am a HTPC apostle (I will try not to preach) and use a HTPC for music also... I realize this makes some cringe but I am not talking SBLive noisy PC's here... approach with an open mind and you will find many putting a PC up against source and pre pro and finding results that equal lexicon / theta / etc... Plenty of threads including ABX etc I can post.

I agree with Larry in that I wont despute this persons findings but I do dispute his conclusions... Unless I missunderstand I dissagree with Larry that EAC is not the best tool for the task due to the fact that when EAC hits an error it REREADS repeatedly the sector to try and get a clean read.  This is done to attempt to get questionable sectors back to certain status.  This solution alone would show that a PC ripping solution that incorporated error suppression (as opposed to error correction) has an advantage over a transport that is forced by its realtime nature to attempt an error correction.

I have had some interesting discussion with Bill Gaw who claims to prefer his ripped archive over his transport or direct PC dirve.  After much soul searching we came to the possible conclusion that as ripped audio is passed as data over the IDE channel and only clocked in the soundcard (at the closest possible point to the DACs) that this could either be eliminating jitter or reducing it to a lower point than his transport or PC based drive was doing.  I should note that this is using the DAC's in the soundcard not his lexicon.

[Felipe]

Hi

Well, for you out there that want results, this is what i found for now:

I made some copies in Black CD's from some of my original ones.
I used a dedicated hard disk, my CDROM has 100% accuracy on reading the files - at least they are all equal , i tried to extract the tracks 2 or 3 times.
The only thing i didnt folow by the book was the recording, because my Nero only let me record at 4x minimum. So instead of 1x i ended up with 4x recordings.

Maybe my system doesnt show diferences, maybe the Black Disk thing is very subtle or maybe i got to record some discs in 1x speed. Thing is ... i didnt note any difference. Yes...the original sounded like the Black.


So...ill try some more and let you know... cheers all.

Oh...PhatPhreddy ! I added your msn contact to my list, i hope we can talk about HTPC - HOW CAN YOU MAKE A PC SOUND LIKE A LEXICON ??

[EchiDna]

Oh...PhatPhreddy ! I added your msn contact to my list, i hope we can talk about HTPC - HOW CAN YOU MAKE A PC SOUND LIKE A LEXICON ??

check out 'the square circle' found in the indox page of this forum... it's where the HTPC and computer based audio crowd hang out

[Tyson]

Also, my comment above about the black disks tracking better is in comparison to copies I've made on other CD-R blanks, not to the original CD's.

I have heard copies sound better than the originals, but it was from the "audiomaster" copy mode on my Yammy CD recorder, not from the media.

[Larry]

Now,  what you are saying is that when we are copying the CD in a CDROM drive to a hard disk, we are correcting the errors that are possible to correct ? Always ? Or must we use a special software like the one mentioned above ?

Do the CDROM drives correct the errors even when simply copying the .WAV to hard disk ?

There are a few layers of error correction in the process of reading and playing CDs. The first frontier is the CD drive, which has various error correction built on it. How good this frontier is deponds on individual manufacturers. Let's say some small errors would be corrected on the drive. For large errors, the drive may or may not report the errors to software, depending on the mood of the day the firmware programmer is. If the software receive error report from the drive, some higher level error correction and error concealment could take place in software. (Software itself can detect certain errors as well)

Both, hardware and software, will do some job to correct errors. So, the conbinations of them make differences, plus your music CD player to make it more complex. We have no way to know all the details of which hardware does what and  does not do what and which software does what and does not do what. There is only standards on what error correction techniques have to be implemented on data of tracks but there is no standard to regulate hardware and software manufacurers on what has to be done and how well to be done and where. Only experiement on individual's specific setup can tell what works or does not work.

CDROM dirves (including CDR and CDRW) and music CD drives are very different devices though CDROM and music CD drive both can read music CDs. Generally speaking, CDROM drives are much more complex than music CD drives, looking at differences of the circuitry attached to them and the weights (we know some people buy amplifiers according to weights).

Having understood that, what I would do is:

1) use the step one and step two to check the reading and writting quality of CDROM reader and writter. This is to make sure reader and writter hardware would not add more errors to the track while reading or writting.

2) try some softwares like EAC and others on various media types say black dyed CDR. If it works (copy sounds better), that means the music CD player has problems to read some pressed music CDs perfectly or detect and correct errors properly. If it does not, that means the music CD player works well.

Badly pressed CDs have better chances to make differences and good CD players have less chances to make differences.

So if you have to try hard on your setup to find any differences, get some low quality CDs, pressed roughly and with a rough surface etc, like those $5 CDs for sale at Sanity. And also your music CD player should have some problems reading all CDs of various quality. I would say most of consumer CD players are very simple, comparing to CDROM drives in terms of optical, mechanical, control, electronics and error handling. It would be very interesting to see how copies compared to the original on a high end CD players like Linn CD12, costing US$20,000, or Wadia's combination of its transport and DAC, dubbed Decoding Computer. Such costing CD players must not show any difference between the copy and the original! Do a simple calculation here. If we put all the CD reader and writers, harddisc, Pentium chips, windows, ripping software that make a good copy into a Linn player, we still have US$19000 to spare.

So, the difference of the copy and original that people could hear is based on some weakness of our particular CD player, either being deficiency of the unit or jerry-build. If everything works as it should, no differece would show. (The only exception is that if the errors are results of CD pressing and uncorrectable but detactable, smart software programmers may make the copy sound better with sophisticated error concealment than the error concealment implemented in the music CD player, which is normally very simple. If this is the case, the new model of the CD player should incorperate it but we have to prepare to pay. Then, no difference any more. However, some smarter one may invent even better error concealment and an even more expensive new model of CD players ..., however, this is under the condition that the CD pressing results in particular patterns of errors. If CD pressing and CD players are all perfect, no differecce in any cases! There is no error then there is no error. No matter how well one can correct errors, no one can correct more than others if there are no errors to correct at all. )

[Larry]

I made some copies in Black CD's from some of my original ones.
I used a dedicated hard disk, my CDROM has 100% accuracy on reading the files - at least they are all equal , i tried to extract the tracks 2 or 3 times.
The only thing i didnt folow by the book was the recording, because my Nero only let me record at 4x minimum. So instead of 1x i ended up with 4x recordings.

No worry, Felipe. Your CD player may work perfectly so that no difference. No difference is good news.

But also bear in mind that there are more reasons not to have any differences or not to tell the differences if there are some, than to have differences or to tell the differences.

This is an area like speaker cables or copper or silver grand debate. I believe in both sides for what they observed.  There are enough reasons for making differences and for not making any differences. Whether making any difference or I can tell any difference on my system in my room to my ears, I got to try. If it does make a difference on my system, I will seriously consider replace my CD player, if it doesn't cost me something like Linn CD players to not make any differences. I would guess a reasonably good CD player should not show a too obvious difference.

[Larry]

Also, my comment above about the black disks tracking better is in comparison to copies I've made on other CD-R blanks, not to the original CD's.

That makes sense that black CDs are later development than silver, gold, blue etc. There must be some reasons to develop new products like black CDRs, having already other colors around. I believe the colors are not to attract kids to buy. Long time back I have learnt that gold CD is good for data and blue CD is good for music. (when there was no black CD then) At that time what I guessed was that gold has good extensibility so that the formation that carries data may last longer or better chance to survive bending or expansion and extraction of temperature changes etc while the CD player laser pick up may prefer a darker background to perform. Talking about this, I recalled that some people said that they could tell the difference of a warm CD and a cold CD. Try it by just putting a CD into fridge for sometime and play it when it is still cold. One more area for poeple to kill time by A/B comparing and arguing.   (I believe the temperature can make some differences considering that it does not need big deformation to change the reflection property of a 0.8um pit. Well, whether anyone can tell the difference on one's system by listening, I will leave it to everybody to comment.)

If someone happens to find, say, silver CDRs sound better than black CDRs on one's setup, also don't be too surprised, just as some people swear the silver sounds better than copper while others never agree.

For me, I may not do a lot A/B comparisons on this myself in this case, but next time when I shop CDR for music, I will get black CDR, just in case.

[SamL]

Oh...PhatPhreddy ! I added your msn contact to my list, i hope we can talk about HTPC - HOW CAN YOU MAKE A PC SOUND LIKE A LEXICON ??

Hi Felipe,

Check out the avs forum.
They got a very active HTPC forum

http://www.avsforum.com/avs-vb/forumdisplay.php?s=&forumid=26

Have fun,
Sam

[Phat Phreddy]

I didn't want to hijack the thread so I avoided posting these links but as you have been given a AVS referal anyway here goes...

http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=236215

http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=164109&highlight=theta

Plus if its a new concept the guys here http://www.carillondirect.com/clnweb/index.jsp?country=UK appear to be making all the right tweaks and modifications right out of the box.

[Phat Phreddy]

Larry, its obvious you do have a firm knowledge of what you are discussing but I really feel very different about CD (or digital in general) formats up to a certain point.  Firstly I want to make it clear that I am not a 'bits are bits' proponent when it comes to a full system (anywhere after the SPDIF encoder there is room for better techniques due to SPDIF's inherant single link one way issues and lack of a timing channel but)... While we are discussing the archival / ripping / repressing / movement and control, of the digital PCM signal I just dont buy some of the statements you are making.

Firstly there are so many psychoacoustic elements coming into play with these kind of tests that I really try to be logical about how the process works.  Consider the following as a minor test, for this I will make the stipulation (or at least consider) that the master CD and the blanks are of basic quality and scratch free.

Rip the master with EAC in secure (paranoid) mode... Repeat as many times as you like... Bit compare the files... They are exactly the same !!! The PCM data ripped is repeatedly the same data, thats byte for byte identical.  There is nothing that can be said about that.  I will grant you that a really heavily scratched disk may have questionable sectors but tests I have done have shown me that EAC is incredible at getting the same rip repeatedly, now whether EAC makes the same mistake or whether EAC makes the same error correction is outside of my provability but whatever the result of that is, the CD 'player' will need to do this without the benefit of multiple reads and force an error correction rather than a error supression or whatever we would call it when EAC reads the sector 16 times to see if it gets it the same all 16...

So we have demonstrably proved that the PCM audio is readable from the disk at the highest level of accuracy (if 10 rips are all bit perfectly the same I call that 'perfect') so now we come to the burning phase.  Repeatedly burn multiple versions of this 'perfect' copy onto whatever blanks you choose.  At this point I will acknowledge that is is quite possible that you may find a cheap or poor quality blank that is not well suited to audio and has errors, I conceed the possibility but have not found this myself.  Burn to multiple CDR's of varying color, style, make, manufacture.

Again bit compare the resulting burnt disks against the origional, the HD ripped version, each other.  As yet I have found ALL files to be the same.  If a digital file is bit for bit the same as another and is demostratably provable as such (re rip any of the blanks with EAC again and compare the Rip from original and rip from the 1st gen copy) you have an identical source.  To really hammer this point home (and if you have plenty of time and CDR's to waste), make generational copies.  If there are creeping errors this is where you will find them... Do the above process and rip from the copy, reburn, rerip from the second copy, reburn, do this for a long time now test the nth level copy against the origonal master.  From my testing with clean new CD's there were still bit perfect clones at 5 iterations.... After that I gave up.

So what are the failings ?? Of course the stipulation of a new clean CD master is perhaps a cheat as not all CD's are new and unscratched.  However given the repeatable accuracy of EAC on poor disks (when if reports a bad sector it does so in the same spot whenever it rips the disk) I contend that it is likely to be impossible to get a cleaner rip than that by any means availble to the consumer... Thats a pont of contention and people owning megabuck CD players never agree that a good quality CD or DVD drive provides more accurate (or at least the most accurate possible) reading of the data than thier item.  I again contend that in my opinion that they are still approaching digital audio like analogue audio and this is a mistake.

So am I saying that all CD players or all transports sound the same ?? 100% NO !!! The above is purely the basis of the extraction of the digital data (relevant to CDR brand and color).  The implentation of the output stages is also crucial to the signal that is outputted.  The reason digital transports sound different (IMHO) is that SPDIF is a poor designed solution allowing for timing to be slaved to the source audio clock and is sensitive to jitter through every link and connection in its curcuit.  The output of analogue has so many points that can effect it I wont even start to go down that road but thats all part of the fun.

So why do audiophiles find differences in CDR v master v colors v others.  One of the reasons I propose (and lets take user error of lack of clean ripping out of the equation) is that this listening is done on CD players that dont feature such robust error supression abilities.  CD players do not (AFAIK) have variable read speeds and although they may have a small buffer to retrack a scratch they need to perform error corrections as noted above.  I will also acknowledge that consumer CD players may not like CDR's and have more difficulty reading them accurately (hence need to perform more error correction and signal interpolation / guesswork) with a CDR.  It is my feeling that it is the failure of the CD players extraction method that is the source of the sonic coloration that may be detectible.

Secondly (and this may not be a popular view to verbalize in an audiophile forum) but I find that we are guilty of so much poor controlled testing and that the mental biases and expectations of people play a far greater role than we give them credit for... How many of us have actually done a blind ABX with CDR's and origonals ?? I have tried but the only firm conclusion that resulted was that my girlfriend conlcudes I am nuts !!! even then we have not proved the CDR is at fault only proved that the extraction of the CDR data may not be repeatedly the same with that drive...            

Anyway thats my 2 cents...

[Larry]

Hi, Phat Phreddy,

In above post, I think you did not disagree on any arguements I commented and I basically tend to agree with most of your new arguements, though some of them seem not directly relevant to the subject in question.

On an earlier post,

I dissagree with Larry that EAC is not the best tool for the task

I did not see on what you disagreed with me. I think we both have no dispution on that EAC is good at its task.

[Malcolm Fear]

Hi Phat Phreddy

Regarding CD players, I have a Rega Planet 2000, a friend has an up to date Meridian, both good players. Doing an A/B test, the Meridian is a little better than the Rega. We can all hear this. The difference diminishes when I place my Rega on a Corian shelf with an half inflated innertube underneath. I also have my AKSA GK-1 and AKSA 55 WPC on a similar support system.
We have both been copying our favourite original CD's onto "black" cd's, this last couple of weeks. I have tried EAC (for the copy protected cd's) and CloneCD for non copy protected cd's.
We both can hear an immediate improvement in the black cd (regardless of the software used). We also play "blind" tests with our wives/children. They all pick the difference within 10 seconds, and pick the black as being superior.

[Felipe]

Well, i guess we can conclude then that almost every CD player does errors and it does less errors with Black CD's. Even if i didnt verified it yet, i will try to burn some Black CD's at 1x speed and then report my findings.

That said...and maybe getting a litle off the subject...or not...the perfect reproduction of a CD , is done with any CD brand original or not would be in a PC. That is...if a CDROM reads always the same bits whatever the brand of the CD it would reproduce it perfectly.

Now ...  knowing that a good soundcard like the M-audio 1010 has better DAC's that a Lexicon....using a PC to read and decode (instead of a CD-player even a Meridian or a Theta combo) would be perfect ???

I know this is not a dedicated area in the forum...but there are many ppl that have compared side by side these processors and the HTPC was superior....and if you have in mind that a HTPC can cost 1/10th of $$$....
I know PhatPhreddy thinks this way....what bout the rest of you ? Larry ?

[Phat Phreddy]

I did not see on what you disagreed with me. I think we both have no dispution on that EAC is good at its task.

Sorry Larry it was probably my reading.... I took this post

SamL wrote:
You can skip step one with the correct CD reading software. Try EAC - Exact Audio Copy.
http://www.exactaudiocopy.de/


This CD reading software does a very different job for a different purpose from the step one of checking reading quality and it cannot tell what the step one tries to tell.

This type of the software tries to correct the erorrs while reading. That's why the author found different software sounds differently.

The step one tries to check the hardware reading quality before any touchs on the music by software. If to check CDROM drive's quality, do step one and avoid using any software like this, otherwise the results touched by this type of software have to be interpreted differently. The errors reported by this type of software may not be caused by the reading CDROM drives, in the other hand, errors caused by reading may not be reported, so that it does not tell how well the CDROM drives or CD writers do the reading.

I still am a touch confused but perhaps you were refering to the alternatives to EAC when stating "avoid any software like this"... Anyway I have no need to argue... It was me that probably missread it...

Again though EAC does not perform error correction... If the drives firmware does not perform error correction (and it is my understanding that it should not but...) then EAC reports all faults as it attempts to reread multiple times until it is sure that any suspect sectors are what it believes...