Copying audio CD with dd/cdrecord produces unplayable CD

[Joerg Schilling]

Yuri <yuri at rawbw.com> wrote:

> Joerg Schilling wrote:
> > Well, you should not expect to get a usable read
> > result from dd.
> >   
>
> Why?
> Handbook recommends the use of dd for audio CD ripping.

Well, then the handbook is sub-optimal.

dd in general does not work at all to read CD-Audio;
FreeBSD is an exception with repect to the fact that you get data at all.

Here is a list of cons for dd even on FreeBSD:

-	dd may not work with all drives

-	Do you know what byteorder you get from a MMC CD-ROM drive 
	on FreeBSD/Sparc? You would need network byteorder on Sparc
	but the MMC CD-ROM drive delivers intel byteorder due to a 
	bug in the MMC standard

	cdrecord always asumes network byte order for RAW audio data,
	this is reasonable

-	Why would you deal with raw audio data at all if there are
	audio file formats that include a notation for byte order and
	sampling rates?

-	There is no jitter check and no quality control with dd on FreeBSD,
	cdda2wav works on all OS and has jitter control and qualiti control
	with e.g. libparanoia.

-	There is no way to get the correct CD structure back if you use dd.
	Cdda2wav reads meta-data and puts them into *.inf files.

-	With dd, you cannot read intentionally defective media as sold by 
	the music mafia.

Allowing to read CD-DA using dd on FreeBSD is a nice gag but nothing I would
recommend in order to create a copy from an audio CD.



Jörg

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