Could a small magnet affect a burned CD?

[Finch Platte]

I made these dinky fridge magnets (1"x1") to include w/ a CD I had burned and put it right up against the CD to ship it.

Will this affect the disc in any way, do you think?

fp

NP Escape Hammer (not the name of a band, but a present I got for Xmas. It would be a good band name. I'll have to start one, just so I can use it.) :rolleyes:

[Dusty Chalk]

Yes (http://www4.head-fi.org/forums/showthread.php?s=&threadid=38792)

[Hyfi]

Yes (http://www4.head-fi.org/forums/showthread.php?s=&threadid=38792)

In a commercial cd there is a pc of non-magnetic aluminum encased in a plastic. The pits and flats are either pressed, pits 0-zero or left alone, flats 1-ones. In PC burners, marks are burned onto a photosensitive die on a substrait that is ecased again in plastic.

So, what is magnetic here? Nothing! However, plastics can build up a static charge. What is the laser looking for? Flats or Pits. How does the magnetism effect a laser looking for a relection or no reflection.

If all of this demagnatizing snake oil is true, why do lower end Phillips CD Players use a magnet as a clamping mechanism along with the spindle to hold and spin the cd? These drives account for a major part of the cd player market, nomatter what brand you think you bought.

It would seem that right after you use your $200 Bendini Ultra Crapalizer, you stick the disk into your $129 cd player and magnetism is introduced to your disk once again.

I tried to get answers to this question on other boards but no results.

Finch, most likely your disks will be fine.

[dld]

Agree with HyFi. Whats a magnet gonna do, reshape the pits? Nahhh. I got a big, big, heavy magnet, gonna try it on Coma Divine tonight.

[Dusty Chalk]

Back-pedal: Finch, most likely, the CD will be fine.

To clarify my earlier post -- please note that the link to which I linked expressed both sides of the controversy (IIRC). Yeah, I know, there's a lot of believers of snake oil on Head-Fi, and they may have seemed to have won, but that doesn't mean that I am convinced.

My beliefs: the foil gets magnetized (or demagnetized), and this affects the (metal) electronics of the CD player. No, it does not affect the optics directly, only in the overall play mechanism indirectly. However, this should be very minor, to the point where most people will not be able to hear the difference. That much, I do agree with.

But if you're worried, just tell them to demagnetize the disc first, and no problem.

[Hyfi]

Back-pedal
My beliefs: the foil gets magnetized (or demagnetized), and this affects the (metal) electronics of the CD player. No, it does not affect the optics directly, only in the overall play mechanism indirectly. However, this should be very minor, to the point where most people will not be able to hear the difference. That much, I do agree with.


Have you ever tried it? Using an old fashion bulk tape eraser should do the same thing if anyone wants to try. I would almost agree with your theory of the little static charge in the plastic, not the aluminum foil, influencing the mechanism except for the fact that the majority of lo-fi players use a magnet and steel for clamping purposes. Hmmm, is that why High End players sound better? I have yet to look inside one that costs more than $450 such as my Marantz 67SE(made by Phillips) and an older Phillips player. Both used the magnet clamp but the 67SE is far superior in sound having to do mainly with the electronics and not the drive, since I believe they both use the CDM7 drive assembly.

I would be interested to test these theories someday since I did spend a year on the cable board argueing about whether you can hear the difference between cables, whether for better or worse. I believe there is a big difference between Rat Shack interconnects and Synergystic or Transparent cables. I belive my higher end Tara labs sound better than XLO-PBJs that someone lent me. Could I tell you which was which in a DBT? Not sure but I could tell you that they were switched.

Dusty, funny your first answer was a big YES. Then you point to a forum that has indefinite proof on both sides of the story. Then you backpedal. Do you have the means to test this theory? What drive assembly does your player employ? Feel like pulling the cover off to see if yours is one of the drives I mentioned? BTW if you are using a top loader like a Rega Planet, your drive clamps the disk differently.


Hyfi........this sure beats whining

[dld]

flippin Coma Divine CD still plays. Experiment unsuccessful

[Finch Platte]

Send it to me for further inspection.

Thanks,

fp

[dld]

Only after I get my Kitaro comp....

[jack70]

When I first saw FP's question and a single reply (DC), I thought Dusty had answered it with a nice simple "NO"... (which would have been my answer).

Oh well..

Hyfi is correct that this a chemical reaction that's on (in) the CD. It's either from silver/gold (photo-etching) or aluminum (from laser [temperature] burning), but they're all NON magnetic. Even if they (lands & pits) were magnetic, the amount of coercitivity/flux needed to effect such tiny pits would be enormous. As long as you don't have a cyclotron in your basement or work at CERN, I wouldn't worry.



My beliefs: the foil gets magnetized (or demagnetized), and this affects the (metal) electronics of the CD player. No, it does not affect the optics directly, only in the overall play mechanism indirectly. However, this should be very minor, to the point where most people will not be able to hear the difference. That much, I do agree with.

That makes absolutely no sense to me at all... I have no clue what you're getting at(?). The signal is coming off the CD from an optical stream of digital data, and then is error corrected digitally and converted digitally. How does non-ferous foil get magnetised? How does "magnetism" effect "metal electronics" anyway?

As for more expensive CD players and why they're (marginally) better...
That has to do with many internal electronic systems that are (1) done more substantially (not on a simple chip/IC), and (2) done redundently, and (3) done with better mechanicals (more detail and closer tolerences, different materials). With such "better" internals, you'll get better accuracy of the data. Even simple circuits cost a lot more when you use discrete components and specialized (more exacting) topograpies. It's much cheaper to put as much of that circuitry on a chip and mass produce it. That's why computers and TVs are so cheap... they'd cost tens & hundreds of thousands to build without mass-produced chips. For example, the electronic innards (circuit boards) of a cheap $100 VCR would cost you thousands of bucks in time and discrete components if you built it with military-spec components and independent supplys etc. You save all that by sticking it all on a few chips, but you lose a bit of quality too... but it's inconsequential considering the totality of the quality of the system (VCR). There are LOTS of sub-systems and circuits that can be optimized if one wants to spend extra time and money... for most listeners (and source material) it's not cost effective to mass produce hundreds of thousands of those (slightly better) systems.



I would be interested to test these theories someday since I did spend a year on the cable board argueing about whether you can hear the difference between cables, whether for better or worse. I believe there is a big difference between Rat Shack interconnects and Synergystic or Transparent cables.....

You realize just what a can of worms that topic is on hi-fi boards? The truth is (IMO) that different cables CAN effect the sound differently... the problem is that most devices that are interconnected by them are different also (their natural electronic poles & transfer-functions) which make getting any REAL answers (listening results) all the more crazy (impossible really). There are simply too many variables to isolate. MOST of the cable hype is just that... hype. Often, certain cables will match a certain system and improve certain audible things. But I've yet to see any of those hacks who sell em agree to a double-blind test where they face losing a finger or toe if their "golden ears" fail a chi-square statistical test. In other words, they won't/(will put their foot where their mouth is. If their "truth" was so obvious, they wouldn't hesitate. They're only in it for the money...

[arc_light]

Many thanks Jack for saving me from having to post a similar, long response that my hunt and peck keyboard skills make it not worth the time and effort.
Foil won't accumulate a charge, and even if it could a fridge magnet wouldn't do it.