*Exact* copy of an audio CD?

Can Mac OS X (10.2.x) clone an audio CD exactly?

I just started with this CD:

[blanc:~] fz% ls -lAn /Volumes/Audio\ CD
total 1080316
-r--r--r-- 1 99 99 4937 Sep 26 08:27 .TOC.plist
-r--r--r-- 1 99 99 32050784 Sep 26 08:27 1 Audio Track.aiff
-r--r--r-- 1 99 99 28605104 Sep 26 08:27 10 Audio Track.aiff
-r--r--r-- 1 99 99 35409440 Sep 26 08:27 11 Audio Track.aiff
-r--r--r-- 1 99 99 30324416 Sep 26 08:27 12 Audio Track.aiff
-r--r--r-- 1 99 99 28212320 Sep 26 08:27 13 Audio Track.aiff
-r--r--r-- 1 99 99 31815584 Sep 26 08:27 14 Audio Track.aiff
-r--r--r-- 1 99 99 26490656 Sep 26 08:27 15 Audio Track.aiff
-r--r--r-- 1 99 99 28593344 Sep 26 08:27 16 Audio Track.aiff
-r--r--r-- 1 99 99 29560016 Sep 26 08:27 17 Audio Track.aiff
-r--r--r-- 1 99 99 35385920 Sep 26 08:27 18 Audio Track.aiff
-r--r--r-- 1 99 99 31316960 Sep 26 08:27 2 Audio Track.aiff
-r--r--r-- 1 99 99 32881040 Sep 26 08:27 3 Audio Track.aiff
-r--r--r-- 1 99 99 33370256 Sep 26 08:27 4 Audio Track.aiff
-r--r--r-- 1 99 99 29569424 Sep 26 08:27 5 Audio Track.aiff
-r--r--r-- 1 99 99 32605856 Sep 26 08:27 6 Audio Track.aiff
-r--r--r-- 1 99 99 30893600 Sep 26 08:27 7 Audio Track.aiff
-r--r--r-- 1 99 99 28863824 Sep 26 08:27 8 Audio Track.aiff
-r--r--r-- 1 99 99 27172736 Sep 26 08:27 9 Audio Track.aiff

dragged all its tracks from a Finder window into an iTunes playlist (iTunes "Get
Info" shows them as "AIFF audio"), and burned that playlist as an audio CD. The
result is:

[blanc:~] fz% ls -lAn /Volumes/Audio\ CD\ Copy
total 1092196
-r--r--r-- 1 99 99 4937 Sep 26 08:35 .TOC.plist
-r--r--r-- 1 99 99 32408288 Sep 26 08:35 1 1 Audio Track.aiff
-r--r--r-- 1 99 99 28962608 Sep 26 08:35 10 10 Audio Track.aiff
-r--r--r-- 1 99 99 35766944 Sep 26 08:35 11 11 Audio Track.aiff
-r--r--r-- 1 99 99 30681920 Sep 26 08:35 12 12 Audio Track.aiff
-r--r--r-- 1 99 99 28569824 Sep 26 08:35 13 13 Audio Track.aiff
-r--r--r-- 1 99 99 32173088 Sep 26 08:35 14 14 Audio Track.aiff
-r--r--r-- 1 99 99 26848160 Sep 26 08:35 15 15 Audio Track.aiff
-r--r--r-- 1 99 99 28950848 Sep 26 08:35 16 16 Audio Track.aiff
-r--r--r-- 1 99 99 29917520 Sep 26 08:35 17 17 Audio Track.aiff
-r--r--r-- 1 99 99 35390624 Sep 26 08:35 18 18 Audio Track.aiff
-r--r--r-- 1 99 99 31674464 Sep 26 08:35 2 2 Audio Track.aiff
-r--r--r-- 1 99 99 33238544 Sep 26 08:35 3 3 Audio Track.aiff
-r--r--r-- 1 99 99 33727760 Sep 26 08:35 4 4 Audio Track.aiff
-r--r--r-- 1 99 99 29926928 Sep 26 08:35 5 5 Audio Track.aiff
-r--r--r-- 1 99 99 32963360 Sep 26 08:35 6 6 Audio Track.aiff
-r--r--r-- 1 99 99 31251104 Sep 26 08:35 7 7 Audio Track.aiff
-r--r--r-- 1 99 99 29221328 Sep 26 08:35 8 8 Audio Track.aiff
-r--r--r-- 1 99 99 27530240 Sep 26 08:35 9 9 Audio Track.aiff

i.e., each track has exactly 357504 bytes added to it. Why?

On the other hand, if I make a disk image of the CD using Disk Copy (File > New
> Image from Folder or Volume, Image Format: DVD/CD master), the track sizes
are unaltered -- but then, going from memory of previous experiments, burning
this to CD with Disk Copy (File > Burn Image...) does not make a playable audio CD.

Is there another way, using stock Mac OS X software?

In article <9MadnaKAC6kKqumiU->, <>
wrote:

> Can Mac OS X (10.2.x) clone an audio CD exactly?
>
> I just started with this CD:
>
> [blanc:~] fz% ls -lAn /Volumes/Audio\ CD
> total 1080316
> -r--r--r-- 1 99 99 4937 Sep 26 08:27 .TOC.plist
> -r--r--r-- 1 99 99 32050784 Sep 26 08:27 1 Audio Track.aiff
> -r--r--r-- 1 99 99 28605104 Sep 26 08:27 10 Audio Track.aiff
> -r--r--r-- 1 99 99 35409440 Sep 26 08:27 11 Audio Track.aiff
> -r--r--r-- 1 99 99 30324416 Sep 26 08:27 12 Audio Track.aiff
> -r--r--r-- 1 99 99 28212320 Sep 26 08:27 13 Audio Track.aiff
> -r--r--r-- 1 99 99 31815584 Sep 26 08:27 14 Audio Track.aiff
> -r--r--r-- 1 99 99 26490656 Sep 26 08:27 15 Audio Track.aiff
> -r--r--r-- 1 99 99 28593344 Sep 26 08:27 16 Audio Track.aiff
> -r--r--r-- 1 99 99 29560016 Sep 26 08:27 17 Audio Track.aiff
> -r--r--r-- 1 99 99 35385920 Sep 26 08:27 18 Audio Track.aiff
> -r--r--r-- 1 99 99 31316960 Sep 26 08:27 2 Audio Track.aiff
> -r--r--r-- 1 99 99 32881040 Sep 26 08:27 3 Audio Track.aiff
> -r--r--r-- 1 99 99 33370256 Sep 26 08:27 4 Audio Track.aiff
> -r--r--r-- 1 99 99 29569424 Sep 26 08:27 5 Audio Track.aiff
> -r--r--r-- 1 99 99 32605856 Sep 26 08:27 6 Audio Track.aiff
> -r--r--r-- 1 99 99 30893600 Sep 26 08:27 7 Audio Track.aiff
> -r--r--r-- 1 99 99 28863824 Sep 26 08:27 8 Audio Track.aiff
> -r--r--r-- 1 99 99 27172736 Sep 26 08:27 9 Audio Track.aiff
>
> dragged all its tracks from a Finder window into an iTunes playlist (iTunes
> "Get
> Info" shows them as "AIFF audio"), and burned that playlist as an audio CD.
> The
> result is:
>
> [blanc:~] fz% ls -lAn /Volumes/Audio\ CD\ Copy
> total 1092196
> -r--r--r-- 1 99 99 4937 Sep 26 08:35 .TOC.plist
> -r--r--r-- 1 99 99 32408288 Sep 26 08:35 1 1 Audio Track.aiff
> -r--r--r-- 1 99 99 28962608 Sep 26 08:35 10 10 Audio Track.aiff
> -r--r--r-- 1 99 99 35766944 Sep 26 08:35 11 11 Audio Track.aiff
> -r--r--r-- 1 99 99 30681920 Sep 26 08:35 12 12 Audio Track.aiff
> -r--r--r-- 1 99 99 28569824 Sep 26 08:35 13 13 Audio Track.aiff
> -r--r--r-- 1 99 99 32173088 Sep 26 08:35 14 14 Audio Track.aiff
> -r--r--r-- 1 99 99 26848160 Sep 26 08:35 15 15 Audio Track.aiff
> -r--r--r-- 1 99 99 28950848 Sep 26 08:35 16 16 Audio Track.aiff
> -r--r--r-- 1 99 99 29917520 Sep 26 08:35 17 17 Audio Track.aiff
> -r--r--r-- 1 99 99 35390624 Sep 26 08:35 18 18 Audio Track.aiff
> -r--r--r-- 1 99 99 31674464 Sep 26 08:35 2 2 Audio Track.aiff
> -r--r--r-- 1 99 99 33238544 Sep 26 08:35 3 3 Audio Track.aiff
> -r--r--r-- 1 99 99 33727760 Sep 26 08:35 4 4 Audio Track.aiff
> -r--r--r-- 1 99 99 29926928 Sep 26 08:35 5 5 Audio Track.aiff
> -r--r--r-- 1 99 99 32963360 Sep 26 08:35 6 6 Audio Track.aiff
> -r--r--r-- 1 99 99 31251104 Sep 26 08:35 7 7 Audio Track.aiff
> -r--r--r-- 1 99 99 29221328 Sep 26 08:35 8 8 Audio Track.aiff
> -r--r--r-- 1 99 99 27530240 Sep 26 08:35 9 9 Audio Track.aiff
>
> i.e., each track has exactly 357504 bytes added to it. Why?
>
> On the other hand, if I make a disk image of the CD using Disk Copy (File >
> New
> > Image from Folder or Volume, Image Format: DVD/CD master), the track sizes
> are unaltered -- but then, going from memory of previous experiments, burning
> this to CD with Disk Copy (File > Burn Image...) does not make a playable audio CD.
>
> Is there another way, using stock Mac OS X software?
>
The answer can be found here:

http://www.cdrfaq.org/

at 4-18-1.

Regards,
Rob.

wrote:


>>dragged all its tracks from a Finder window into an iTunes playlist (iTunes
>>"Get
>>Info" shows them as "AIFF audio"), and burned that playlist as an audio CD.


>>each track has exactly 357504 bytes added to it. Why?


> The answer can be found here:
>
> http://www.cdrfaq.org/
>
> at 4-18-1.


Thanks for the URL, but D'oh!, I just noticed that I had iTunes > Preferences >
Burning set to add a 2-second gap between songs. I guess that's the explanation, no?

This suggests that (except for the added gap) the tracks are indeed bit-for-bit
copies. But the above ref gives all kinds of (to me esoteric) reasons why they
shouldn't be so. So, which is it?

In article <lVadnU8zSKKUO-miU->, <>
wrote:

> wrote:
>
>
> >>dragged all its tracks from a Finder window into an iTunes playlist (iTunes
> >>"Get
> >>Info" shows them as "AIFF audio"), and burned that playlist as an audio CD.
>
>
> >>each track has exactly 357504 bytes added to it. Why?
>
>
> > The answer can be found here:
> >
> > http://www.cdrfaq.org/
> >
> > at 4-18-1.
>
>
> Thanks for the URL, but D'oh!, I just noticed that I had iTunes > Preferences
> >
> Burning set to add a 2-second gap between songs. I guess that's the
> explanation, no?

Yes, that would be an explanation for the extra bytes added.

> This suggests that (except for the added gap) the tracks are indeed
> bit-for-bit
> copies. But the above ref gives all kinds of (to me esoteric) reasons why they
> shouldn't be so. So, which is it?

Defenitely the 2 second gap, but it could also be other explanation.
The only way to really tell would be to compare the actual audio data
from the original with the copy. However, it's very unlikely that the
human ear would be able to tell the difference.

Rob.

>> Burning set to add a 2-second gap between songs. I guess that's the
>> explanation, no?

You'll never get a truly exact copy with iTunes. The closest you can
get in osx is with the unix command line app cdrdao, easily installed
via fink.

hwolf <"Hugh Wolf"@deutsches.lieder.de> writes:

> You'll never get a truly exact copy with iTunes. The closest you
> can get in osx is with the unix command line app cdrdao, easily
> installed via fink.

You could also use dd(1):

# dd if=/path/to/cd/device of=somefile.iso bs=2048

'if' stands for "input file", 'of' for "output file", and 'bs' for
"byte size". By default it grabs 512-byte chunks; CDs however store
things in 2048-bite chunks so it makes the accesses more logical. You
can try higher values of 'bs' to see if you get faster transfers.

From the FreeBSD manual page:

DD(1) FreeBSD General Commands Manual

NAME
dd -- convert and copy a file

SYNOPSIS
dd [operands ...]

DESCRIPTION
The dd utility copies the standard input to the standard output.
Input data is read and written in 512-byte blocks. If input
reads are short, input from multiple reads are aggregated to
form the output block. When finished, dd displays the number of
complete and partial input and output blocks and truncated input
records to the standard error output.

You should be able to access right away from the Terminal.

--
David Magda <dmagda at ee.ryerson.ca>, http://www.magda.ca/
Because the innovator has for enemies all those who have done well under
the old conditions, and lukewarm defenders in those who may do well
under the new. -- Niccolo Machiavelli, _The Prince_, Chapter VI

In article <>, David Magda wrote:
> You could also use dd(1):
>
> # dd if=/path/to/cd/device of=somefile.iso bs=2048

The problem with this is that you won't be able to do anything with
the 'image'.

Hugh Wolf <> writes:

> In article <>, David Magda wrote:
> > You could also use dd(1):
> >
> > # dd if=/path/to/cd/device of=somefile.iso bs=2048
>
> The problem with this is that you won't be able to do anything with
> the 'image'.

Why? You should be able to burn it just fine: it's raw data.

I've duplicated data CDs using this message by telling the software
it was a straight ISO 9660 image. I don't see why this would be
different for audio CDs (admittedly I haven't tried).

--
David Magda <dmagda at ee.ryerson.ca>, http://www.magda.ca/
Because the innovator has for enemies all those who have done well under
the old conditions, and lukewarm defenders in those who may do well
under the new. -- Niccolo Machiavelli, _The Prince_, Chapter VI

In article <>, David Magda wrote:
>> The problem with this is that you won't be able to do anything with
>> the 'image'.
>
> Why? You should be able to burn it just fine: it's raw data.

Audio cds aren't organized the way data cds are. That's what makes
the copy problem hard in the first place.


> I don't see why this would be
> different for audio CDs (admittedly I haven't tried).

Try it. If you can get it to work, by all mean lets us know. But I
don't think you will. If it was this easy, there would never have
been a need for specialzed tools like cdrdao and Exact Audio Copy in
the first place.

David Magda <dmagda+> wrote:
> Hugh Wolf <> writes:

>> In article <>, David Magda wrote:
>> > You could also use dd(1):
>> >
>> > # dd if=/path/to/cd/device of=somefile.iso bs=2048
>>
>> The problem with this is that you won't be able to do anything with
>> the 'image'.

> Why? You should be able to burn it just fine: it's raw data.

> I've duplicated data CDs using this message by telling the software
> it was a straight ISO 9660 image. I don't see why this would be
> different for audio CDs (admittedly I haven't tried).

One reason you won't be able to use it is because the data format for
an audio CD is different from a data CD. The sectors on a CD actually
are something like 2700+ bytes long. On a data CD, 2048 bytes of data
are recorded in each sector, the remaining bytes are used for holding
a long error detecting and correcting code. Audio records some 2500
bytes of digital data, and uses a smaller error checking code. When
reading a disk normally, the CD drive just delivers the audio data or
regular data minus the error checking codes. Unless you have software
and a drive that can deliver the raw sector data, you can not get an
exact duplicate. Using dd to copy is also not going to get what you
want off of an audio disk.

Joe Heimann