Helicon said:
How?! The Yamaha copies the CD bit for bit with NO compression!
Yes, but especially if the CDs are less than perfect, some errors will take place. I haven't tried using the yamaha, but certainlyripping files to my harddrive using my CD drive and NERO, and also using an old marantz CD writer to burn tracks to CD, copies were not bit-for-bit identical with the originals (though, except on v scratched CDs, differences were v minor - and certainly not audible to me).
Exact Audio Copy tries to avoid this problem. As its website puts it "In secure mode, this program reads every audio sector at least twice. That is one reason why the program is so slow. But by using this technique non-identical sectors are detected. If an error occurs (read or sync error), the program keeps on reading this sector, until eight of 16 retries are identical, but at maximum one, three or five times (according to the error recovery quality) these 16 retries are read. So, in the worst case, bad sectors are read up to 82 times! But this will help the program to obtain best result by comparing all of the retries. If it is not sure that the stream is correct (at least it can be said at approx. 99.5%) the program will tell the user where the (possible) read error occurred. The program also tries to adjust the jitter artefacts that occur on the first block of a track, so that each extraction should be exactly the same." (
http://www.exactaudiocopy.de/)