Hi there, The theory is simple - in bit-for-bit perfect copy there is no loss of information. Period. However, if there is an error during the copy process, the CDR or CDRW can still play and the error correction software in the player can mask it - hence the degradation in performance. Even a click or a skip in extreme cases - this is a due to a big error not corrected by the player. On the other hand, a copy can sound BETTER than the original. Simple explanation - the amount of jitter introduced during recording can be LESS than the amount of jitter on the original. The huge buffers in computer CDR burners can help exactly with this. They buffer the signal from the original CD, and use the computer own clock as a sync signal when writing to the copy. The clocks in computers run at 10-100 times higher rate of the synch signal of the clocks in ordinary players and DACs. Consumer players/recorders combos often don't have these big buffers, run at 10 to 50 Mhz (as opposed to up to a GHz or more in computers) and can introduce more jitter. Especially at high speeds. Hope you know how jitter translates into signal degradation during payback... To summarize: given the following: - bit-per-bit perfect copy - no errors during copying - the same or smaller amount of jitter in the copy - AND - your player can read wihout a hickup (e.g. reads 100% of all bits recorded) there is simply no way the copy can sound worse than the original. If anyone hears a degradation the reasons could be: - introduced more jitter in the copy - there are errors during the copy process or it is otherwise not bit-per-bit perfect copy - player can't read all bits properly so it has to "guess" and interpolate the signal - OR one's just hearing things... Hope this helps a bit. Please, visit http://www.digido.com/jitteressay.html for more info. I'm in no way affiliated with the folks there - I'm just an EE and signal processing major with a mid-fi system that supports the theory - in most cases there is no difference to my ears... Regards, Kocho
- ...
- 152 posts total
- 152 posts total