glen999
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Copy a CD
ampnut
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Oops ! I forgot to login, before posting.

The above post is by me.

ampnut

Monty
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I burn CDs using Nero and as WAV files with very good results. Without picking nits, the copy is way better than I would have expected.

As a reference that you may be familiar with, it sounds a lot better than dubbing cassettes.

glen999
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Hi Monty,

1)is it exactly same quality?

2)how about exact copy from CD to CD without converting to WAV or other type of format? will any sound loss?

Monty
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No, it isn't exactly the same quality, but the differences aren't in ways that are immediately objectionable and probably not even noticeable to most people. If you are very familiar with a particular recording, you will likely notice degradation.

I really don't have much experience burning CDs and then comparing them in my system. I've done it, but most of the time, I'm burning compilation CDs for my car. Needless to say, I'm not in a critical listening mode in my car.

I think there are too many people on the forums with gobs more experience than I to address the CD copying formats. I don't do Ipod, download tunes or buy music in a streaming format. If I like something, I buy the disc or record. The guys who do buy the downloads have a much better frame of reference for achieving the best sound from transfers and should chime in shortly.

As far as copying goes, color me impressed.

ampnut
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Quote:

how about exact copy from CD to CD without converting to WAV or other type of format? will any sound loss?

A direct CD to CD copy will not correct for any read errors.

Exact Audio Copy infact re-reads any sector that has been read with an error, untill its error free.

The direct CD to CD sound, to my ears is not only flat ( sound stage ) but also hard..

CECE
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How come my Philips CD Recorders say in teh manuals, it's a direct exact copy of teh original. As in identical, there is no sound difference between copies and original.

ampnut
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To my ears, the Philips CD recorder ( which copies Only on Audio CD Blanks ) makes the best copies.


Quote:

How come my Philips CD Recorders say in teh manuals, it's a direct exact copy of teh original. As in identical, there is no sound difference between copies and original.

Didnt these guys also say that the CD ( 1st Generation ) dics and player, provided perfect sound forever.... or something to that effect ?

If that was true, there really is no need for SACDs or DVD-A.....

Cheers !

JoeE SP9
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I have found that the DVD burner in my computer makes better copies than the CD burner in my computer. They still don't seem as good as the original but the ones from the DVD burner are closer. No, I don't know why. I use EAC to make copies.

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Interesting....

Unfortunately, I gave away my CD burner, when I upgraded to a Plextor DVD burner.

I susect the DVD burner's capability to focus on & burn smaller pits has something to do with it ?

CECE
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Didn't Edison impress people with the first generation of recorded music? So far teh original CDs are still playing, on it's way to FOREVER. and it sounds just like it did when new, so it must be perfect forever. Of course SACD is an improvment, but it doesn't negate the fact that the original CD is still playing after 20 years, just like it did when I bought them. Even LP's are reissued with re mastering and improvments of sound. The CD storage is more "forever" than an LP which is being worn out with each use. so there is no problem with teh statemtn they made. But let's see in 50 years, if they will still play., as I am perfect listener forever.

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HHB Burnit PLUS makes perfect copies, using CD-R or anything else. Tascam DV-RA1000 too. so do my Philips units. Without the use of any magic wires too.

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Quote:

A direct CD to CD copy will not correct for any read errors.

Exact Audio Copy infact re-reads any sector that has been read with an error, untill its error free.

The direct CD to CD sound, to my ears is not only flat ( sound stage ) but also hard..

Audio contains data. basically, it's just a data copy.
It has to be same.
For example, an executable file in a CD.
If we copy one file from one CD to another CD (Note:copy without conversion to other formats), the file must be identical. otherwise, the file will not run correctly.

ampnut
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1. It can only copy/ write what it has read.

If it has a read error, that error will be written..... and the copy will not be 'Exact'

Perfection in the real world is always elusive....

2. I am no expert on the topic, but I recall reading that audio CDs have an intrinsically different format, which allocates a different ( less ? ) amount of sp[ace for error correction.

Hence the error correction ( and extent of Data robustness ) of an audio CD and data CD, are quite different.

Could someone more knowledgable on the topic throw some light ?

Thanks

FRANKe
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Quote:

Audio contains data. basically, it's just a data copy.
It has to be same.
For example, an executable file in a CD.
If we copy one file from one CD to another CD (Note:copy without conversion to other formats), the file must be identical. otherwise, the file will not run correctly.

That

ampnut
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Hi FRANKe,

Thanks for your VERY informative post. MUCH appreciated.

I am using a Plextor DVD Burner (PX 716A) on my m/c at home. Not sure how it performs on Audio CDs.

However, with the long Easter weekend kicking in from tomorrow, I will certainly run the tests.

Also any info ( URL ? ) on jitter measurement software ( preferably any freeware ) would be very helpful.

Also, as you mention, the quality of the CD quality will also depend on the blanks used.

Further, CDRs have a lower reflectivity ( ? ) due to their greenish hue, than regular, silver stamped CDs.

Audio players are probably not optimised to read CDRs, ( unlike Computer CD drives ). Hence when CDRs are used in an audio player, they will probably yield higher errors and jitter than what a computer benchmark test would indicate ?

Thanks once again for a wealth of info.

Cheers

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Hi Frank,

That was a great post and really helped to clear the air of a whole lot of misconceptions people and audiophiles have about digital audio.

With that in mind here are a couple of more things to consider.

Early generation CD players were not able to properly read CD-Rs not because of the "lower reflectivity" of CD-Rs but because of the shallower pit depth on a "burned" CD. The later generation CD players have had their laser mechanisms adjusted to properly read these shallow pits and can therefore play CD-Rs without problems.

I think you need to futher clarify the difference between a data CD and an audio CD. The difference you wrote of is only on the software side and not on the hardware side. What I mean is that the same blank CD-R can be used to create a data CD-R or an audio CD-R, there is absolutely no physical difference between the two discs - it is all marketing BS.

And now a few things to really blow the minds of my fellow audiophiles.

Not only can one copy a music CD, one can take a music CD, "rip" the music onto one's hard drive as wav files, use a lossless compression program like FLAC to compress the wav files to flac files, use a parity checking program like Smartpar to ensure data integrity and upload the flac and par files to a newsgroup.

Now someone clear across the world can download those files, parity check them (and repair them as required), decompress them back to wav files and then burn them to an audio CD-R which will be an exact copy of the original music CD. Not bad, eh?

A similar thing can be done with a DVD except the amount of data being transfered is much greater and the process takes much longer. Now you know why the music and movie industries are so upset.

By the way, one can also use file sharing/transfer programs like Bit-Torrent to do the same thing I outlined above.

FRANKe
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Quote:

Also any info ( URL ? ) on jitter measurement software ( preferably any freeware ) would be very helpful.

Certainly.

PlexTools, of course, comes with Plextor drives and is useful for reporting C1/C2 errors. But when it reports jitter, it only shows an arbitrary graph with no corresponding values or percentages. This is why I use PXScan.
http://www.alexander-noe.com/cdvd/px/index.php
This is a freeware program designed specifically for Plextor drives, but it

ampnut
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Quote:

jazzfan said:

Early generation CD players were not able to properly read CD-Rs not because of the "lower reflectivity" of CD-Rs but because of the shallower pit depth on a "burned" CD. The later generation CD players have had their laser mechanisms adjusted to properly read these shallow pits and can therefore play CD-Rs without problems.

I am not so sure of this.

Based on the excellent pointers by FRANKe, I have spent the better part of the day, today, with PX Scan and PX View.

I have scanned Original CDs and CDRs.

The Original CDs I scanned are :

Cafe Blue - The FIM Glod Version CD.

Jaime Valle - 'Round Midnight SCAD Hybrid CD

George Michael - OLDER. ( a regular silvered CD )

The CDRs scanned were Buddha Bar ( Disc 1 ) which was archived on my HDD as wav files.

& a few other CDRs, all written from EAC generated Wav files.

Surprisingly, the CDRs had deeper pits than the George Michael - OLDER !

I currently have a CEC belt transport ( Very Old version) This does not read CDRs, but works perfectly with original CDs.

It reads the George Michael - OLDER CD, but None of the CDRs.

Hence I suspect that the drive readability is more closely linked to the surface reflectivity, than pit depth ?

Comments and suggestions / thoughts most welcome.

Thanks again to FRANKe and jazzfan.

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Hi again,

Sorry about the misinformation, it seems you were right about the lower reflectivity being the cause of CD-R incompatibility with some older Cd players. Below is a quote from Wikipedia.

Readability in CD drives

There was some incompatibility with CD-Rs and older CD-ROM drives. This was primarily due to the lower reflectivity of the CD-R disc. In general, CD-ROM drives marked as 8x or greater will read CD-R discs. Some DVD players will not read CD-Rs because of this change in reflectivity as well.

Sorry for the mistake.

ampnut
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Hi jazzfan... no need to apologise, Im learning all the time, and all inputs further that.... even lateral or obtuse thoughts that have emerged on other topics on this forum ;-)

FRANKe, you wrere correct, my CDRs seem atleast as good as some pressed CDs....

However, at the risk of sounding obstinate, I still feel that the CDR copies lack 'air' 'ambience' and 'emotion' of the original.... even on my rather humble setup ( Denon 2900 + Prima Luna PL-2 + Sonus fabor Extremas )...

Would be nice to hear views from other forum members too.

Thanks & Cheers

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Quote:
Hi jazzfan... no need to apologise, Im learning all the time, and all inputs further that.... even lateral or obtuse thoughts that have emerged on other topics on this forum ;-)

FRANKe, you wrere correct, my CDRs seem atleast as good as some pressed CDs....

However, at the risk of sounding obstinate, I still feel that the CDR copies lack 'air' 'ambience' and 'emotion' of the original.... even on my rather humble setup ( Denon 2900 + Prima Luna PL-2 + Sonus fabor Extremas )...

Would be nice to hear views from other forum members too.

Thanks & Cheers

Since you asked....

For what it's worth, I have never noticed any difference in the sound quality of a copied audio CD-R when compared to the original audio CD, or for that matter even a copy of a copy. Most of my copies are made using either EAC or Nero. In fact I have a CD-R copy (burned from flac files) of the Mobil Fidelity Sound Labs gold disc version of Pink Floyd's "The Wall" which holds its own quite nicely when compared against the original vinyl copy on Columbia played back on my Linn LP-12 turntable. So much for the sound of "gold" CDs.

While I can't argue with the various test results showing the lower error rates of different brands of CD-Rs, different burn speeds, different CD burners, etc. I'm just not that convinced that these lower error rates translate into "better sound". If the red book specification allows for 200 errors per second before failure than one should assume that any good CD player can handle lower error rates without any adverse affect on the audio output. However, it seems to me that we're rehashing ground well covered in the early days of digital audio. Perhaps some Stereophile editors can point us to some articles in the Stereophile web site's archives which would shed some light on this subject.

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Quote:

If the red book specification allows for 200 errors per second before failure than one should assume that any good CD player can handle lower error rates without any adverse affect on the audio output.

Audio CDs, with their (only) 2 levels of error correction, AND the limitation of No Re-read in case of a bad read, does provide scope for sound deterioration from CD less than pristine CDs.

FRANKe has posted an excellent para on the C-1 & C-2 levels of error correction.

He also pointed me to the PX Scan site, which has an informative manual....

Here is an exerpt that is technical but informative anyway :


Quote:

2.1 Errors on CDs
When scanning a CD for errors, you get several error values: C1, C2, CU12. In order to
understand what those numbers mean and how to judge whether or not a CD has been
recorded at good quality, you need to understand, at least a little bit, how data on a CD is
arranged and protected against damage.

A CD consists of sectors of 2352 bytes each. A sector is split into 98 groups of 24 bytes each.
For each of those groups 4 bytes are calculated and used for C2 error correction. Then, after
moving around some data, 4 more bytes are calculated for each group of 28 bytes and are
used for C1 error correction.

When reading a CD, there are 32 bytes (24 + 4 + 4) in each of the 98 groups. If one bytes
is damaged, you have an E11 error, if 2 bytes are damaged, you have an E21 error, if more
than 2 bytes are damaged, you have an E31 error. E11 and E21 errors are guaranteed to be
corrected using C1 error correction only. If there are more damaged bytes, the result after
doing this ’moving around’ backwards is that those errors are then distributed over several
groups of 28 bytes each, hopefully with not more than 2 errors per group. One error in such
a group is called an E12 error, 2 errors are called an E22 error (also called C2 error), more
than 2 errors are called an E32 error (also called CU error).

On audio CDs, an E32 error means that error concealing techniques might be necessary in
order to minimize the risk of ticks and clicks on playback. Thus, an audio CD that contains
E32 errors could be damaged beyond repair (the original data cannot be retrieved anymore)
and should immediately be backuped. A CD containing E22 errors but not E32 errors is not
yet damaged beyond repair, but you might want to make a backup before E32 errors show up.

On data CDs, there is a third layer of error correction (that’s why you only have 2048 bytes of
data in one sector of a data CD), so that a certain amount of E32 errors can still be corrected.

On CDs, error measurement is usually performed over an interval of one second, which equals
75 sectors. Very good discs can show an error rate below one C1 error per second and no
C2/CU errors.

Clearly, its not just that 200 errors per second will be corrected. If the errors are sequential, as explained above, C-1 & C-2 just cant handle it....

Monty
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Years ago, Robert Harley had an article in 'phile that discussed, among other things, CD disc quality in the manufacturing process.

In the article, Harley observed and measured the ability of the disc to construct the pits and lands in the writing process. In particular, he found that some disc writing would create sharply defined pits and land while others would round the pits and land and noted a difference in sound quality.

It would seem that there are a lot of areas that come into play in creating a high quality write to disc.

eagle
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I believe I just read in Stereophile that if you use "audio" blank cds that the copy will sound better. It has something to do with the technology of the original v. the copies tech.

eagle
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I use Nero's "copy to cd" option, which does the copy and the rewrite all at once, even if you only have one drive. It copies the original, then asks you to put the blank in the drive. It's easy and works well.

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