What is the functional significance of C1 and C2 errors?


From my readings here, I understand that C1 and C2 error rates are a very good quantitative measure of CD burn quality.

I also understand that both C1 and C2 errors are corrected by the reading drive (is this also true for a regular CD player?) and that burned CDs with high inital C1 and C2 error rates will degrade at a more rapid rate (is this because the baseline is elevated, or is the actual rate of deterioration accelerated?).

I ask these questions because I just checked a CDR (Sony type 1 cyanine that was in the glove compartment of my car is south Florida for about 2 years) that shows massive errors on Nero CD Quality Check, but still appears to function perfectly well (word processing documents and digital photos - some of the digital photos may (?) be slightly washed out and seem to be grainy, but the effect is subtle and I don’t know if I could pick these defects out in a double blind test).

Also, has anybody tested any very weathered audio CDRs to see if there is any audible degradation in sound quality because of high heat and humidity? (should corrected C1 and C2 error rates have any effect on sperceived sound quality?).

Any insights would be greatly appreciated!

quantitative measure of CD burn quality

Not really, they are read errors, and the quality of the burn is only one factor. They can be the result of several variable factors coming together to create reading problems. They do not physically exist on the disc, in other words. Nor do they directly affect the quality of the data, as long as they are corrected. How well a drive corrects them is what may or may not affect the data, for example if they are “incorrectly corrected”. Most drives can correct them up to a point, but where that point is will be different in each drive. Audio data and plain data are 2 different things in terms of correction, and again it all depends on the drive.
Whether you can hear a difference between a crappy audio disc and a good one is a hotly debated topic, and the answer probably lies in other things besides C1/C2 errors.

I think that most Sony CD-Rs (that come up as Sony Corp. in ATIP reading programs) are made by Lead Data which is crap media.

I have Sony 48x that shows as Acer media. I think the older Sony media is different.

4 years ago, there was Sony 6x media by Taiyo Yuden