pfarrell Wrote: > Then run a binary diff program on both the original and reconstituted > one. Know of any binary diff programs for OS X and/or UNIX in general? If there are differences, I presume the binary diff program would tell me whether the differences are just zero-blocks?
Alternatively, has anyone already done this check for ALAC? =) pfarrell Wrote: > Of course, are 20 year old CDs going to stay readible? AFAIK, they should be. I think my oldest CD is only about 16 years old, but it's still doing just fine. Burned media has a problem in that it uses organic dyes that break down over time, especially when exposed to heat or light. With stamped CDs, the data is stamped into the plastic substrate and then coated with aluminum for reflectivity; as long as the plastic remains sealed and the aluminum does not oxidize, it should last "forever." 'According to wikipedia' (http://en.wikipedia.org/wiki/Laserdisc), LaserDiscs were manufactured in a slightly different way, namely that the *aluminum* was stamped and then sandwiched between plastic. If the plastic were not properly adhered, the aluminum could oxidize and cause rot. It's not actually "bit rot," though, because LD was apparently an analog format... therefore any defects in the aluminum (e.g. from oxidization) would be immediately noticeable, much like a scratch on vinyl. Since CDs are digital, they can employ error correction to work around small defects (though large scratches obviously still cause problems). (Apparently early CDs did suffer from rot due to improper manufacturing - I guess the oxidization there got so bad that even error correction couldn't fix it.) pfarrell Wrote: > Whether any devices will read CDs and still be connectable to a computer > in ten years is a more realistic concern. That's certainly true. However, it doesn't look like DVD-related formats are going away anytime soon (BluRay and/or HD-DVD players will retain backwards-compatibility with existing DVDs, and therefore VERY likely with existing CDs as well). Since it is essentially "free" to keep backwards-compatibility with older media for technologies such as BluRay/HD-DVD (the underlying laser technology is quite similar), I suspect CDs will be readable in computers for at least another 5-10 years, as long as we're still using similar media (e.g. BluRay or HD-DVD). pfarrell Wrote: > So keep that 2005 Mac around for ancient recovery duties. Well, I think we'll have plenty of warning before CDs become truly obsolete... it certainly won't happen overnight, and I doubt within the next few years, so I'll probably be safe with a 2009 or 2010 Mac. =) And obviously before buying a new computer, I'll KNOW whether its optical drive can read a CD or not, so I can make the decision to keep the older machine at that time. =) -- cepheid ------------------------------------------------------------------------ cepheid's Profile: http://forums.slimdevices.com/member.php?userid=3845 View this thread: http://forums.slimdevices.com/showthread.php?t=22635 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/audiophiles
