Why does the copy sound better than the original

the problem with the question is what does "better" mean ?

i have heard copies i prefer to the original and i have originals i prefer to the copy.

if prefer connotes "better", than the question has no answer, because of the subjective nature of the judgment.

Al, thanks for providing the explanations. However, I think it's worth considering that even for very low jitter players and CDs that are brand new without scratches this phenomenon of the copy being better than the original seems to apply. Obviously read until correct players are in a separate category. I suspect the explanations provided - e.g., black CD-Rs, jitter, noise, wobbly CD, Etc. - are simply Strawman arguments and that noone has actually investigated this phenomenon beyond mere speculation.

Al, I didn't take the time to read the threads you mentioned, but (my understanding is) this was settled a long time ago; and the overwhelming conclusion (at that time anyway ;~) had to do with the fact that a burned CD has (physically) real 'pits' -- which are actually 'burned' into the media with a laser, producing a more easy-to-read surface -- i.e., less digital 'jitter' in the resulting datastream.

Commercial CD's are stamped (ironically, just like an LP!) so their so-called 'pits' are really just depressions (or was it bumps?) that scatter the reflected laser light enough to make it look ("read") like a pit to the playback sensor. Whereas a recorded CD (with 'real' pits, literally burned into the surface,) produces a much cleaner (jitter-free) signal on playback.

Probably ripping software is doing a good job there. :)

Cd-rs have an ink layer that is darkened by a writing laser. My experience with cd-rs is they become unreadable if they are exposed to light over a period of time. You can leave one sitting in the sun to demonstrate this effect in a shorter period of time.