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Worthwhile CD-R Media?
isdnip asks: "I've noticed that when I burn a CD-R, it's basically a random chance whether or not it will play on any given CD player or CD-ROM drive. Blank CD-Rs are dirt cheap nowadays, but the costlier gold ones are not available at retail, if at all. So which ones now on the market are most likely to work? They seem more interested in bragging about maximum speed, not quality. Does a high speed rating help or hurt readability (I usually only burn at 2x or 4x)?"
"Just for example, I've had pretty good luck with Maxell 'CD-R pro' blanks, mediocre luck with 'IBM' licensed-brand media, and even worse results from Memorex, which had the dubious distinction of looking most like real gold, though really just based on an ordinary dye layer. I don't want to buy a 50-pack of junk. I haven't seen any magazine reviews, either. I'm sure Slashdot readers have had a wealth of experience which we could all stand to share."
Dan's data has an article which explains CDR quality very nicely
At first, it focuses mostly on strangely colored and oddly shaped cdrs, but at the bottom it has some VERY useful information, including a little utility called cdrid, which identifies WHO REALLY makes the cdr disk. It turns out many differently branded disks are actually made by the same company.
The article also points out that cdrs with a darker dye in them work better. I tend to agree from experience. Typically, I buy Sony CDRS from staples... they're pretty cheap and work good. I also found that the sony ones work fine in most car cd players, while cheap ones don't work at all.
(By the way.... a Plextor 24x burner is only about $150 now... i find that burning cds at lower speeds doesn't improve compatibility, execpt for with cheap disks; but my burner only works up to 8x, so i dont know how faster ones fare). But beware: make sure your drive supports BuRN proof or something similar. There is nothing more aggrivating then having to burn a cd twice because of a buffer underrun.
-- If you try to fail and succeed, which have you done? - Uli's moose
The unplayable CD may well still be readable due to the quality of the tracks which were written. I.e. if the writer (and subsequent reader) have a fairly narrow read path (beam) and fairly sensitive pickup, then they can read even a shoddy job of writing. (Note that higher-speed equates to a narrower and spectrally shallower track).
As such, the drive which can't read it probably has a wider beam and/or a less sensitive pickup.
But if you put that same disk back in a CDRW drive (like the one which wrote it) you'll find that it reads just fine. (Kind of like a floppy drive being out of alignment, only in this case the "alignment" is a matter of quality of beam reflection rather than magnetic field).
To move on...
Media is, as mentioned elsewhere, only made by a couple of manufacturers, BUT they also make a number of different levels of quality which are then sold and branded by anybody/everybody.
So how do you tell? Most cd-burning software nowadays will tell you what the media is, but that doesn't help much in the store. (Er, excuse me, can I burn one of these just as a test? Yeah, I'll tape the box back up nice and neat if they suck...)
So you have to judge by color. Unfortunately many of the top-side decals/coatings used in the branding process have a color of their own (hence light-green phthalocyanine dye often appearing blue or dark-green).
In general, a CDRW will give MUCH better cross-drive compatibility than a simple CDR due to the higher sensitivity of the dyes and the better quality reflective surface behind.
Which brings me to cheap CD's. Real CD's have an aluminum surface sandwiched between two plastic disks. A CDR actually needs an extra set of layers because the dye isn't reflective! It has a silver backing which is laid on top of the second layer of plastic. Now a few people will disagree and say it's on the same layer as the dye which is sometimes true, but most of the manufacturers have switched to having it be on the other side (outside) of the plastic sandwich as it makes for a much lower level of defects. But this means that you really have to have the final decal with the cutesy branding/artwork/whatever to protect the silver!
Super cheap (blank silver) CD's will very often scratch very easily on the top surface. I've even seen a few that you could smear the silver off with a firm rub of your finger tip.
Evil...
Bad...
Stay away...
So cheap is fine s'long as they're CDRW's (or at least the darker CDR's) and they have a top decal (or 3rd layer of real plastic for the fancy-schmancy folks).
Finally, burn slower! Cut 20% off your drive's rated speed (or the CDR's rated speed if it's slower) and you'll get much better burns. Manufacturers of drives and media alike advertise the best possible numbers they can get away with. If your drive's beam is a little under-powered and the dye on that batch of CD's is a little thin, then a reduction in speed will make for a lot fewer toasters, er, coasters.
(I've been playing with OSX too much, I can tell!)
Enjoy!