[X4U] importing audio CD as AIFF

[DZ-Jay]

Michael Winter wrote:
> 
> I'm still struggling with why that wouldn't work in practice.
> 

Mainly because you are thinking of an audio cd in terms of a list of 
files, like reading a floppy disk, or a hard-disk, or any other media 
with a file-system.  An audio CD, as originally designed by Philips and 
Sony, contains a stream of data representing samples of the original 
audio signal.  They are stored in blocks on the disc, and decoded by the 
drive when read.  In order to make a duplicate of the disc -- an exact 
copy -- you need to copy all data, block by block, from the disc.  There 
are technical reasons why this is difficult, but mostly it is not done 
by commonly used software for political reasons, i.e. to prevent 
wholesale piracy.  Because of this, most software that copy Audio CDs 
merely decode the data and encode it into a different format that can be 
interpreted easily by other standard audio applications, such as MP3, 
Apple Lossless, WAV, and AIFF.  Then, in order to burn a new copy, it is 
necessary to decode the new file and re-encode it into a stream of 
samples of the audio signal to put on the CD.  During this process, data 
can be lost, depending on the decoding/encoding process and the interim 
format selected.

Here's more information that might be useful.
http://www.pcguide.com/ref/cd/formatCDDA-c.html

That is why a software application that performs raw DAO (Disc-At-Once) 
copying is required to make an exact duplicate.  Here's a technical 
article explaining what it does:
http://forums.afterdawn.com/thread_view.cfm/23595

	dZ.