Please keep in mind that I am new to the digital world and I'm just curious about something....
I have just recently bought two Dac's. As I've been trying to break them in, I've had a cd player spinning a cd 24/7 on repeat into the dac.
I'm wondering, does the cd laser constantly going over the same pits over and over again, somehow degrade the physical aspect of the cd layer that is being read by the laser?
I know that I wouldn't want to replay my precious vinyl over and over again, but in that case I'm physically dragging a diamond stylus through the record grooves.
I have no idea if the laser does anything to the bits it's trying to read when kept on 24/7?
There are a lot of reasons why CDs fail to play correctly.
A case of "CD rot" -- i.e., oxidation of the aluminum layer -- is very, very rare in all but the earliest replicated discs. It can be identified with the naked eye as black layers of oxidation that slowly spread across the metal layer. The change in reflectivity is what makes the oxidized areas unreadable.
The cause of this is leakage of air onto the surface of that thin layer, usually through physical damage (like extreme flexing) or because of manufacturing QA failures.
If you don’t see black aluminum oxide patches on the reflective surface of a misbehaving disc, there’s a different reason why the CD is not playing correctly.
Much of this, btw, doesn’t apply to recordable CDs -- which use far more sensitive dyes -- and to early DVDs, which are more susceptable to oxidation because of their multi-layered physical construction. It also obviously does not apply to gold CDs, since oxidized gold has the same color and reflectivity as elemental gold.
I can't speak authoritatively to the point, but I'd expect that, barring physical damage, oxidation "rot" is unlikely on any disc manufactured in the last decade or two.
Well I own over 3,000 cds ,I don't stream.Buying them now for like a buck and that's cd sets also ,box sets to,Crazy.I only buy ones with not scratches. I find people who used a cd player in there cars using have then scratched like crazy.I found some that need good cleaning with 70% alcohol.Removes growth on them.They play great again.i own 6 cd players. The only trouble I had with one was years ago .I had an Onkyo high priced one .I had bought when cds first came out .It lasted 5 years Tried to get it replaced, but It couldn't be fixed.When I think I used to buy cds for $16 bucks or more or cd box sets for 50,60 bucks ...WOW.
I owned a small recording business and would routinely furnish my clients with copies of their performances that were burned with a pro level CD recorder. On rare occasion I would get a complaint of "drop-outs" on the disc. At first I attributed it to the clients using an inferior machine for playback but I finally traced it back to the discs themselves. That is when I switched exclusively to "Archival" quality CDs. The phthalocyanine dye or ink used on these discs is remarkably stable and even extended periods of exposure to sunlight will rarely cause them to default. Since making that switch, I have only had one problematic archival disc and that was one that refused to initialize. Have I checked every disc I made since then ? Of course not, but I've received zero reports from clients that the disc performed poorly. I'm sure that stamping a disc is more reliable than burning a disc but that is what we have available at present.
Update. I played this CD on a second system with the same result. This background noise could be best described as what you would hear with a really dirty old abused LP. The second CD of this box set played fine.
Never ever had an issue with my CD’s. That is, until right after this thread was posted!
Last night played "Miss Saigon" and heard this low level crackle/static noise. At first thought it was my electronics. Thankfully other CD’s played fine.
Many years ago, when I was a contributing editor to various mainstream tech publications, I did a large feature on disc rot. Spoke at length with engineers, large manufacturing & fab facilities, the whole nine yards. At this point, I don’t remember where it was published, maybe PC Magazine.
The bottom line is that "CD rot" today is pretty friggin’ unlikely. There were reports that the first generation of CDs were subject to this problem, and it was eventually traced back to a single disc-fab plant, I think in Europe, that was a source for discs worldwide. The issue was an improper seal that allowed air to contact the aluminum layer, causing black oxidation. This, of course, changed the reflectivity of the pits & lands, making parts of the disc unreadable. Most people I spoke with believed that this happened only when the disc was flexed or otherwise abused to the point of breaking the original seal. My conclusion was that this was an exceedingly rare occurrence, very much overplayed in the press.
Note that I’m talking about replicated discs. Home-recorded recordable CDs, for some reason, are much more susceptible to this problem. But again, it seems as though the issue was mostly with earlier generations of recordable media and, even in worst case, it would take years to manifest. Much more common than silver-disc "rot", but still pretty rare. My personal opinion (and it's just an opinion, not something I can verify) is that the greater number of problems with recordable CDs has more to do with the fact that they use potentially degradable photoreactive inks. But at this point, who knows?
This shouldn’t be confused with "DVD rot," which was technically similar, but much more common. DVDs are composed of multiple layers of plastic glued together, and are thicker. In terms of physical structure, they’re more susceptible to damage by flexing. This problem was exacerbated by early DVD jewel cases, which made it more likely that unthinking users would flex the heck out of a disc while trying to pry it out of the case.
Again, this was a problem related to early manufacturing issues, that were later worked out. And although more common than "CD rot", which borders on urban legend, it was still pretty rare.
I have examples of "rotted" discs still sitting on a shelf somewhere. If I get the chance, I’ll take some pictures & post them here so you can see what "rot" looks like.
I own thousands of discs . I had a few early CDs, and several CDRs, that bronzed, but they play and I still listen to them . The few CDs that I thought might have deteriorated all were cured with a good cleaning
Physical CD degradation does happen, but media should last 100 years+. If you are concerned, you can always rip into file then burn another copy. Or just play the file.
Don’t forget that the easiest surface to damage is the label side. The pits are just under it! And most CDs are stamped, not laser burned!
Hard to see how the tiny currents in a DAC will help it burn-in. Speakers, cartridges and amplifiers possibly. I put an input power meter on my Krell class A amplifier after a rebuild, and the power consumption definitely rose over a few days, even though it was switched off when not in use.
Of the few hundred CDs I’ve owned since the late 1980s only one quit working, and that wasn’t long after I bought it. To this day I’m not sure if it was really defective, or if I somehow damaged it.
I'd be more concerned about the CD players becoming obsolete and no longer made, like VCRs.
While I have had CD’s go bad because they weren’t constructed properly, the aluminum inside has corroded and or air pockets have formed, I’ve never had one go bad from use. Misuse maybe, but not laser induced wear.
@no_regrets many "experts" (e.g. professional audiophile reviewers; electronic engineers; neuroscientists; etc.) would argue that break-in or burn-in time for various audiophile sound system components is a myth. Of course, there are some who argue that some amount of burn-in time for some components actually does benefit their performance or sound fidelity. Still others argue that what is happening when someone thinks they hear a benefit of burn-in time for some components is that their ears or, more precisely, the auditory cortex of the brain becoming accustomed to the new sound signature, vis-a-vis the acoustical characteristics of the home or sound room.
In my experience, over the last 5 or 6 decades, I've found that electronic components like amps, DACs and CD players require virtually no or negligible periods of burn-in or break-in time. Although I've never owned or lived with one, I have no trouble believing that very large or very powerful amps need or benefit from warm-up time. However, I have difficulty believing their sound fidelity would improve or benefit from a certain amount of burn-in or break-in time. The non-exotic turntables and cartridges I've owned, similarly, did not seem to need any burn-in time to speak of. However, the TT I have now definitely did benefit from a couple hours of spin time in order for the motor spindle and bearings to become properly lubricated. As for the speakers I've owned and enjoyed over these many years, I think I've noticed very small improvements in some of them (more high-end or expensive ones) after a certain amount of burn-in time. However, a somewhat famous professional audiophile component reviewer who shall remain nameless told me this was all in my head (i.e. auditory cortex). The salesperson who sold me the pair I have now advised they would need approximately 90 hours of burn-in time to reach their full potential. A professional reviewer told me they would need closer to 100 hours and yet another wrote in his review of them that they fully blossomed after approximately 110 hours. Since I had a 30 day return policy from the shop that I purchased them from, I decided to listen very critically and keep a log after I brought them home. Auditory Cortex notwithstanding, it certainly did seem, to me, that there were small improvements over time, mostly in bass response, to a lesser degree in high frequencies and negligibly so in midrange after somewhere around 60 hours.
So, as in all things, let conscious be your guide! However, that being said, I think running your CD player & DAC 24/7 is accomplishing nothing other than wearing out those components.
We service vintage audio gear and frequently have CD players presented with "can't read" error message of some sort. Typically, this is a combination of weak laser and slop in the sled assembly. Sometimes it's difficult to present technical information to customers that they can relate to. So, to be "more relatable" to male customers, I use the following:
"Image trying to hit that little target in the urinal with a weak stream that you can't hold very steady anymore."
Just know that the "energy" of the laser reading the pits and spaces is nowhere near the energy that was used to create them. So, no, you can play a CD a million times and it will be just as good as the first time. This was indeed one of the "selling points" for CDs compared to vinyl album back in the 1980s.
I would worry more about putting unnecessary wear and tear on your CD player in breaking in the new DACs and use a streamer instead set on various playlists that run for hours and hours.
Regarding "CD rot", I have a collection of about 2500 CDs, some from the mid-1980s. Out of all of those I’ve had TWO "go bad" because of oxidation of the aluminum substrate. It was like a small pinhole was somehow created (either a manufacturing defect or caused by rough handling in a car). Fortunately, I was able to find copies still in print and simply bought replacements.
If you’re still at all concerned then just use a cd of music you don’t really like and don’t care if it’s damaged. You must have at least one of those in your collection.
None of my pre-recorded/store bought CDs have degraded unless scratched or otherwise damaged. The CD-Rs that I burned have shown substantial degradation somewhere in the 50% range. CD-Rs contain inks while pre-recorded CDs don't.
The laser will not degrade the CD.
Some CDs get rot as mentioned above.
The only concern I would have would be that it might be getting hot inside the player, and leaving a CD in a hot place for a long time can cause it to delaminate (rot).
Thank you! I appreciate everyone commenting and sharing their thoughts with me on this.
I kind of figured that CD's could possibly remain good for a long time. In fact, I have a lot of CD's that are decades old that are still playing fine.
However, my concern was, if I just leave the same cd in the cd player, playing continuously on repeat 24 hours/day, for several days in a row..... could the laser, due to constantly reading the same cd over and over again while being on repeat.... could "that" deteriorate the performance of that one cd?
I'm getting the impression that it shouldn't be a concern.
Sometimes a CD will go bad with age, an issue known as "CD rot." However, this ties to poor manufacturing practices rather than use. Poor quality control when the CD was made can result in oxidation of the reflective surface. There can also be adhesive bonding issues or the presence of contaminants. However, none of these problems are caused by how many times a CD has been played. End users can still damage a CD through scratched surfaces or leaving the CD in hot sunlight, etc., but again, these are not playback issues.
No. Don’t worry, it will not hurt them. I remember the concern was over age and that the integrity of the info on disks was supposed to be only something like twenty years. I have CDs going back forty years without a problem.
My CDs like my vinyl no longer gets played since streaming now sounds as good or better, cost a fraction, and gives access to over ten million albums. They look nice covering my walls. Don’t forget to consider streaming before investing in any more physical media.
You must have a verified phone number and physical address in order to post in the Audiogon Forums. Please return to Audiogon.com and complete this step. If you have any questions please contact Support.
