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Alex_UK
07-12-2009, 12:13
Afraid to admit that I have never "cleaned" any of my CDs or DVDs other than a quick wipe on my T-shirt/jeans, or on the odd occasion when a disc is really nasty, a normal duster and a bit of Mr Sheen... :o

Any recommendations/tips - I've generally just tried to avoid them getting dirty - handling them carefully on the edges and always putting them away as soon as I've finished, but as some are now getting old, is it worth cleaning them, and if so, with what?

Any suggestions gratefully received!

StanleyB
07-12-2009, 12:22
Wipe the shinny surface with a damp cloth and then with a dry tissue. But don't use the medicated Kleenex tissues! They have a greasy substance on them.
Stay clear of the side with the printing on it. Once that gets damaged you are in trouble.

Rare Bird
07-12-2009, 12:35
http://www.russandrews.com/product-ReVeel-and-ReleeS-pack-5420.htm

Themis
07-12-2009, 13:01
You have to take a look at the reflective surface for dirt/imperfections. If there are none : do nothing.
If there are imperfections, there are errors when ripping. What I do is : put water on the reflective surface (not the printed) or damp cloth then delicately dry them with a dry cloth. Errors disappear. ;)

Rare Bird
07-12-2009, 13:17
I've never found the need to clean a CD..I see no reason why you should have to unless it's second hand.I never ever buy second hand, even the slightest mark on a disc would give me sleepless nights..Now if your a smoker i have no sympathy infact i hope you next shit is an hedgehog if you do

:lolsign:

Alex_UK
07-12-2009, 13:28
I've never found the need to clean a CD

Me neither, really, but as I said, some of them are getting on a bit now especially as...


Now if your a smoker i have no sympathy infact i hope you next shit is an hedgehog if you do

I gave up nearly 2 years ago, so no hedgehog crapping for me - but some of my older CDs could have bronchitis!

Thanks Stan & Dimitri for the tips too. I've blown a whole 3.99 on this CD Cleaning Kit (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=160367669480&ssPageName=STRK:MEWNX:IT#ht_4294wt_1006) from ebay - 2 yes 2 sets for the money! I especially like the little pincers so you don't put fingerprints back on the disc.

The Vinyl Adventure
07-12-2009, 13:30
bloody stupid shiney disks! ;)

St3v3
07-12-2009, 13:43
I have one 'o them there fancy JML CD cleaners that buff and polish. It leaves a disconcerting ring of light scratches on the disc (maybe mine's broken?! :scratch:) but it's great for rescuing them if they're second-hand and the original owner has used them as coasters.

http://cgi.ebay.co.uk/CD-DVD-Disc-Scratch-Remover-Repair-Cleaner-Kit-Machine_W0QQitemZ390123605858QQcmdZViewItemQQptZLH _DefaultDomain_3?hash=item5ad52dcf62

1ryal
09-12-2009, 14:09
My Obsessive Compulsive relationship with my High Fidelity leads me to often clean CDs.

Have found Microfiber cloths good, and will occasional use lens cleaner (for glasses), for the odd CD that has been afflicted by the jam on my children's fingers. I picked up a bottle of "lens shine" on ebay, which seems to do a nice job without leaving a residue.

Have heard of people using isopropyl alcohol, which is also available in wipes at opticians, this also seems to do a nice cleaning job, and has not yet killed any of my CDs

Haselsh1
09-12-2009, 14:58
I went through this over ten years ago whilst dealing in Hi-Fi equipment so here goes...

Take an uncleaned newish CD and breathe heavily on it. The mist on the CD will show up a light pattern all over the disc which is some form of contamination. Now wash the disc in hot soapy water and rinse in hot water. Dry the CD using a piece of kitchen roll or toilet paper wiping in straight lines outward from the centre. Breathe on the disc again and notice... pattern gone...!

Whether this coating of new discs affects the sound quality I have no idea. Maybe someone would like to do exhaustive scientific trials. I'm not.

Mike
09-12-2009, 16:49
WD40 and a belt sander with the coarsest belt you can lay your hands on...... Sorted!

Alex_UK
09-12-2009, 17:07
WD40 and a belt sander with the coarsest belt you can lay your hands on...... Sorted!

Is the resultant metallic dust any good for filling speaker stands? :lol:

Thanks though for all the other sensible suggestions! :ner:

;)

Kris
09-12-2009, 18:50
New CD's/DVD's have a coating of release agent on them. Our (crap) DVD player upstairs is very sensitive. Sometimes it will reject a new disc even though the disc is physically clean. One wipe with Isopropyl and the disc will be accepted.

I also have a friend who couldn't get a disc to work at all. I told them to clean it. They said it was already clean, it was brand new, just out the case. They cleaned it, it worked.

Btw, Isopropyl alcohol is so useful round the house for many things (including cleaning phono plugs, switch contacts etc. A can of lighter petrol and a bottle of Isopropyl should be in everyones tool kit.

Oh, and apparently record cleaning fluid contains distilled water, Isopropyl Alcohol and a non-foaming version of washing-up liquid.

REM
10-12-2009, 17:53
Btw, Isopropyl alcohol is so useful round the house for many things (including cleaning phono plugs, switch contacts etc. A can of lighter petrol and a bottle of Isopropyl should be in everyones tool kit.

Oh, and apparently record cleaning fluid contains distilled water, Isopropyl Alcohol and a non-foaming version of washing-up liquid.

Not all record cleaning fluids contain IPA, some deliberately avoid its use as they believe it may be detrimental to vinyl.

Additionally, it's not that easy to get over the counter these days. Go into your local Boots and ask for some and see how far you get, they will most likely keep you taking whilst they are on the blower to some anti-terrorist spook agency and before you know it you'll be waking up in some weird looking village with a big #6 badge pinned on ya:eek:

Kris
10-12-2009, 18:39
Additionally, it's not that easy to get over the counter these days.

I get mine from ebay or Studiospares.

Primalsea
10-12-2009, 20:21
Maplin sell 1 litre cans of IPA, Supermarkets sell 4 x 550ml cans of IPA as well:)

I've had some discs that got a bit too scratched and bought a CD clening kit from Maplin. It had some general cleaner, a polishing pad, a cloth and something that was pretty much T cut.

It was just the ticket for gently removing scratches. I believe these do cause an effect even if your CDP doesn't skip. The error correction is still kicking in. My old CDP was a bit sensitive to scratched discs.

I plan on buying a lot of used CD's this year so my parents have bought me a battery powered Skip Doctor! Its really for removing scratches, otherwise I second the microfibre cloth.

Incidently I sometimes use baby wipes to get rid of static on my LP's. Works pretty well!!

Alex_UK
11-12-2009, 20:18
Nice one - some great ideas there! Thanks everyone. (Plenty of baby wipes in our house Paul, so that one's a definite experiment!)

Primalsea
11-12-2009, 20:26
Use the clean ones Alex, won't you!

tfarney
29-12-2009, 13:10
It's a shame this kind of marketing is legal:


ReVeel and ReleeS are CD and DVD enhancers that let you experience the full performance from your discs. Use them together and you'll hear an even more detailed and natural sound, with better pictures from your DVDs, too.


The microfiber cloth, and perhaps a few drops of water are all that is needed, but the most they will do is stop your CD from erring due to dirt substantial enough to block the laser from reading the pits in the disc. The idea that a cleaning fluid could provide "a more detailed and natural sound" is either comedy or science fiction. Certainly not science.

Tim

Primalsea
29-12-2009, 17:55
That's cause you have to have your little magic rock sitting on your CD player at the same time. Except on Tuesdays, of course if you happen to have someone in your house called Dave and 2 chickens in the garden.

FFS! get it together man!

technobear
30-12-2009, 18:55
It's a shame this kind of marketing is legal:


ReVeel and ReleeS are CD and DVD enhancers that let you experience the full performance from your discs. Use them together and you'll hear an even more detailed and natural sound, with better pictures from your DVDs, too.


Well I haven't tried those two but I use Auric Illuminator on all my CDs and they do sound more detailed and more natural and less harsh afterwards.

tfarney
30-12-2009, 22:42
ORIGINAL POST DELETED

I should know better than to comment here on posts involving things like disc treatments. Enjoy what you hear.

Tim

Themis
30-12-2009, 22:56
The idea that a cleaning fluid could provide "a more detailed and natural sound" is either comedy or science fiction.
Or both. ;)

Players should have the "interpolation" light, it could be easily seen when it lights up.

Haselsh1
31-12-2009, 17:10
Or both. ;)

Players should have the "interpolation" light, it could be easily seen when it lights up.


The original Cambridge CD2 had that very light. It was a red LED titled 'Error' and it flashed everytime the player made up a digit. It was amazing to watch the thing flashing every so often. The CD2 also had a 'pre-emphasis' LED that indicated when a CD was recorded using pre-emphasis.

Themis
31-12-2009, 18:17
In fact, there are two types of errors :
- interleave, which is entirely corrected due to code redundancy, and
- interpolation, which is recoverable only through "guess-like" algorithms and results into an approximation of what is on the disk.

Interleave is normal, and the CIRC is implemented to manage it (see http://en.wikipedia.org/wiki/Cross-interleaved_Reed-Solomon_coding)

Interpolation is a major error and cannot be corrected. Redbook says the result signal should be "gracely degraded".

If the CD2 shows all errors, this is not of much interest, since only interpolation errors can result to a signal degradation. ;)

technobear
31-12-2009, 19:26
I don't think that the effect of Auric Illuminator or any other CD polish has anything to do with the correctness of the 1's and 0's.

I have found that AI improves the sound of the vast majority of discs I have used it on. These are not dirty or damaged discs. They are pristine discs which will give very few if any read errors.

The reason for the sonic improvement lies elsewhere in the workings of the CD player. I'm sure we could all come up with theories to do with laser mechs, servos, power supplies, regulators and other such fascinating items and I suspect that noise and jitter would form a large part of the discussion but they would all be basically 'guessing' and I don't see the point of that.

Why should we care anyway? :scratch:

Personally I don't give a rat's arse what the reason for the improvement is. I am satisfied that I can hear a beneficial difference and I am thankful that someone has, by whatever means, created this product and put it on sale.

Major flame wars have been fought on other forums between those who have tried the product and can hear the difference and those who haven't tried it (or are cloth-eared :lol:) and insist that it is impossible, science fiction, comedy etc.

This being AoS, we have a somewhat saner approach in that if we can hear a difference then we trust our ears and if you have not tried the product then you are not in a position to comment on its efficacy.

Marco
31-12-2009, 19:36
Hi Chris,

I haven't read through all of this thread, so my apologies if I've missed something, but could the "CD polish" of which you speak be removing mold release agent (see here: http://www.rubbermoldcompounds.com/release_agents.htm), which is applied to CDs during the manufacturing process?

If so, this is a recognised problem and the beneficial sonic effect of its removal is something I've experienced on many occasions :)

Marco.

Themis
31-12-2009, 19:48
Why should we care anyway? :scratch:

It is related to each one's approach. I believe it is sane to try to understand what surrounds us: that's why I always need an explanation. If I can't find it, I will try nevertheless.

In my everyday activities, thereare only people's reactions that I find too complicated to explain. CDs, laser disks and computer software is very simple compared. And related explanations are simple and understandable with basic notions. :)

The fact that in AoS we trust our ears has nothing to do with that : remember Belt ? ;)

Jonboy
31-12-2009, 20:10
Toothpaste and a cd polisher will take out a serious scratch but be carefull it will destroy it if you go to mad.

See here

http://www.amazon.co.uk/s/?ie=UTF8&keywords=jml+cd+cleaner&tag=googhydr-21&index=aps&hvadid=4772873839&ref=pd_sl_6jh87pwhqz_b

technobear
31-12-2009, 20:24
Hi Chris,

I haven't read through all of this thread, so my apologies if I've missed something, but could the "CD polish" of which you speak be removing mold release agent (see here: http://www.rubbermoldcompounds.com/release_agents.htm), which is applied to CDs during the manufacturing process?

If so, this is a recognised problem and the beneficial sonic effect of its removal is something I've experienced on many occasions :)

Marco.

Hi Marco!

AI certainly does remove mould release agent but it is more than that. Afterall, washing up liquid will remove mould release agent but it doesn't exhibit the same effects as AI.

AI is a combination of treatments including the dreaded black pen for inking over the centres and edges of the discs to cut down on stray light reflections, a cleaner and plastics polish and an anti-static treatment.

AI also ships with very fine polishing cloths that are useful for all sorts of things beyond CDs (like dusting gloss black finishes without scratching them).

I'm on my third lot and will keep buying it for as long as I have CDs to treat.

It's much better value sound-for-pound than some other CD treatments like the Audio Desk system CD sound improver (aka. CD lathe) and the Nespa Pro CD finaliser. My experience is that both of those tweaks also work very well and add to what AI does but IMO they cost too much.

AI works out at about 20p per disc.

Marco
31-12-2009, 20:36
It's a shame this kind of marketing is legal:



The microfiber cloth, and perhaps a few drops of water are all that is needed, but the most they will do is stop your CD from erring due to dirt substantial enough to block the laser from reading the pits in the disc. The idea that a cleaning fluid could provide "a more detailed and natural sound" is either comedy or science fiction. Certainly not science.

Tim

The effect of mold release removal perhaps, Tim, rather than any 'voodoo magic'? See my post above.

RA claim that the liquid agent released by their CD wipes, when made wet under a tap, is particularly effective at removing the mold release left on CDs as part of the manufacturing process....

Of course, ordinary water with a little soap may work just as well, but that doesn't detract from the fact that mold release being removed, by any method, makes CDs sound better. I've heard this effect myself before many times :)

Marco.

Marco
31-12-2009, 20:42
Hi Chris,


Hi Marco!

AI certainly does remove mould release agent but it is more than that. Afterall, washing up liquid will remove mould release agent but it doesn't exhibit the same effects as AI.

AI is a combination of treatments including the dreaded black pen for inking over the centres and edges of the discs to cut down on stray light reflections, a cleaner and plastics polish and an anti-static treatment.

AI also ships with very fine polishing cloths that are useful for all sorts of things beyond CDs (like dusting gloss black finishes without scratching them).

I'm on my third lot and will keep buying it for as long as I have CDs to treat.


Cool - you're definitely more dedicated than I am in terms of CD cleaning! :respect:

The point I was making to Tim is that there exists a valid mechanism to explain why CDs would sound better when cleaned. Therefore, regardless of any of the other (debatable or otherwise) effects of your AI, the simple fact that it removes mold release agent from CDs is enough to explain what's going on..... :)

Marco.

Primalsea
31-12-2009, 22:46
There is something in going on with these CD treatments but I dont know for sure that you need the expensive treatments, just standard non residue soap mixtures. My old CD94 would have trouble reading discs if they had even minor scratches or dirt, even if you couldnt see it. Whenever I had skipping disc I would just clean it with a fairly basic CD cleaning kit and later a JML one. Always after a clean the disc would read fine.

I imagine that its not a it wont read / it will read situation. I would think that its the case that the cd get progressively harder to read with the error correction kicking in more and more as well as the mechanism having a harder time to align the pick up mech. Its feasible that these things could degrade the sound in some way.

tfarney
01-01-2010, 03:45
The effect of mold release removal perhaps, Tim, rather than any 'voodoo magic'? See my post above.

RA claim that the liquid agent released by their CD wipes, when made wet under a tap, is particularly effective at removing the mold release left on CDs as part of the manufacturing process....

Of course, ordinary water with a little soap may work just as well, but that doesn't detract from the fact that mold release being removed, by any method, makes CDs sound better. I've heard this effect myself before many times :)

Marco.

Pardon me while I repeat myself:


ORIGINAL POST DELETED

I should know better than to comment here on posts involving things like disc treatments. Enjoy what you hear.

Tim

Themis
01-01-2010, 08:41
I thank Athena that my PC CD-ROM drive doesn't give a damn about disk quality while ripping. Let the CD be clean or not, new or old, Gold or SHM, it will always rip the same. :eyebrows:

Except when there are severe scratches, of course. :(

Primalsea
01-01-2010, 09:47
In all fairness Tim I think you have every right to openly question the marketing claims of these companies.

technobear
01-01-2010, 10:13
What intrigues me the most is that the effect of AI and the other two devices I mentioned can still be clearly heard on a 10 grand Esoteric X-01 SE, a CD player with one of the most over-engineered mechs in existence.

You would think that at this price point, all disc reading issues and any noise-polution issues arising in the transport and maybe back through the power supply into the signal chain or whatever would have been thoroughly addressed.

Then again you might think that jitter would be rendered a non-issue on a 10 grand CD player too. Yet if you plug a laboratory standard rubidium word clock into the back of the Esoteric X-01 SE, the difference is not that subtle.

Marco
01-01-2010, 12:22
In all fairness Tim I think you have every right to openly question the marketing claims of these companies.

Of course he does! :)

I have no problem with that whatsoever, as I'm sure Chris doesn't. Tim's opinion on this is as valid as anyone else's. I was merely offering my thoughts on the matter to provide a little balance.

Marco.

tfarney
01-01-2010, 12:26
In all fairness Tim I think you have every right to openly question the marketing claims of these companies.

It's OK, Paul. Questioning the marketing claims of a company questions what the users of that company's products perceive, and people tend to take it personally. I could have found a much gentler way to say it, or, knowing that
"I don't know but I hear it," is ultimately the answer, I could not have raised the issue in the first place.

Tim

Marco
01-01-2010, 12:52
Tim,

Sometimes people do genuinely hear effects in audio, even though science currently may not have an answer to fully explain them :)

Not everything we genuinely hear with audio can currently be scientifically proven.

The sonic benefits of removing mold release agent on CDs (a deposit left on CDs after the manufacturing process that definitely exists), in my experience, is one of them. YMMV, of course.

Marco.

tfarney
01-01-2010, 13:08
Tim,

Sometimes people do genuinely hear effects in audio, even though science currently may not have an answer to fully explain them :)

Not everything we genuinely hear with audio can currently be scientifically proven.

The sonic benefits of removing mold release agent on CDs (a deposit left on CDs after the manufacturing process that definitely exists), in my experience, is one of them. YMMV, of course.

Marco.

I'm not arguing that people can't hear things that currently can't be measured, Marco. I'm saying there isn't much point in discussing it if, ultimately, the answer is whatever you perceive is real. I didn't see any discussion of the connection between cd quality and mold release in your link, though.

Tim

Marco
01-01-2010, 13:41
That's fair enough, Tim.

The link I provided was simply to show the applications of mold release (and to show it exists), one of which is as a sealing agent applied to CDs at the end of the manufacturing process. It wasn't to show a connection between it and CD playback quality :)

Removing MR on CDs by whatever method, however, in my experience, improves CD playback quality. I can't comment on the efficacy (or otherwise) of any other aspect of the device Chris uses, as I've not tried it.

Marco.

tfarney
01-01-2010, 14:12
That's fair enough, Tim.

The link I provided was simply to show the applications of mold release (and to show it exists), one of which is as a sealing agent applied to CDs at the end of the manufacturing process. It wasn't to show a connection between it and CD playback quality :)

Removing MR on CDs by whatever method, however, in my experience, improves CD playback quality. I can't comment on the efficacy (or otherwise) of any other aspect of the AI Chris uses, as I've not used this particular device.

Marco.

It's used as a sealant at the end of the process? I wonder what it is meant to seal.

From the link, even though it was about the production of things much different than CDs, I would have assumed it would have a similar use in CD manufacturing -- as an agent applied to the mold the CDs are formed in, to allow them to more easily release from that mold upon hardening. It would follow, then, that if the residue of that mold release were any kind of impediment to the laser, the cds would be cleaned prior to burning the data onto the disc, which surely happens after the disc is molded. If not, the effects of the mold release on cd would be written into the file contained on the disc, which would make the later, consumer cleaning considerably more difficult.

But it's not unusual for a product developed for one purpose in one area to be discovered to be useful for something completely different in another. I wonder what mold release is used for in cd production. I may have to look into it when I return this evening.

Tim

Marco
01-01-2010, 14:34
By all means do, Tim, if you feel so inclined.


From the link, even though it was about the production of things much different than CDs, I would have assumed it would have a similar use in CD manufacturing -- as an agent applied to the mold the CDs are formed in, to allow them to more easily release from that mold upon hardening.


You're probably right, so perhaps I've misunderstood the application. However, regardless of that, it's a process that exists, which was the whole reason for me posting the original link.

One of course can speculate with these things until the cow's come home. With the way your mind works (and I respect how you look at things), you always need a 'proven' mechanism to explain why something should happen, and I do understand that.

With me, things are rather simpler... I'm not one for endlessly speculating and pontificating with effects in audio (the 'whys and wherefores', if you will) - the proof of the pudding for me will always be in the listening, despite whatever 'evidence' may exist to 'disprove' the results of what my ears hear.

I need no further 'proof' than what my experienced and discerning ears tell me, so will simply kick back with my favourite music and enjoy the benefits of whatever I've done to improve the sound (whether that be cleaning CDs or whatever). So with hi-fi, it would appear that I get to enjoy a much simpler and easier life than your good self or others of a similarly (endlessly questioning) objectivist mindset... :eyebrows: ;)

Marco.

technobear
01-01-2010, 16:40
...It would follow, then, that if the residue of that mold release were any kind of impediment to the laser, the cds would be cleaned prior to burning the data onto the disc, which surely happens after the disc is molded. ...

No, CDs are not burned. CDs are stamped just like LPs.

The data pits are stamped into the polycarbonate disc using a metal stamper which also moulds the disc (just like a vinyl LP). The stamped side of the disc is then coated with a fine layer of aluminium by vapour deposition. The aluminium layer is then covered with an acrylic layer (spin coated I believe) and the label is printed or silk screened onto the acrylic.

In a perfect world all CDs would be cleaned and polished before they leave the factory but just like with vinyl, this is not done (vinly records also tend to come covered in mould release agent).

In a perfect world all CDs would also be run through a Nespa finaliser.

Sadly we don't live in a perfect world. We live in a greedy one :(

Marco
01-01-2010, 17:00
Useful info, Chris, so thanks for sharing.

I do admire your 'going the extra mile' to obtain the best sound from your favourite tunes. This is *precisely* what AoS is about :)

Marco.

Themis
01-01-2010, 17:30
Are we talking about a one-time cleaning or a regular cleaning here ? :scratch:

Marco
01-01-2010, 17:33
Hi Dimitri,

One time to remove the mold release agent, and periodically after that to remove any built-up fingerprints or dirt, etc :)

Marco.

Themis
01-01-2010, 17:46
I mean, this liquid which is supposed to clean the moulding agent, is to be applied only once, no ?

Is it supposed to remove grease and dirt as well ?
(I am sorry for insisting, I'm rtying to understand so that I could advise this to my friends. I am not directly concerned with neither of this cleaning)

Marco
01-01-2010, 18:06
Yes to both questions :)

Once the MRA has been removed, the effect is permanent. To clean fingermarks, etc, afterwards, just use a microfibre cloth, or whatever your normal cleaning method is.

Marco.

Primalsea
01-01-2010, 18:12
It seems the general idea is to clean new CD's to remove the MR them use the black pen around the peripheries. After that periodic cleaning just to remove grease, dirt and dust that builds up over time.

Its my belief that through cleaning with mild, common cleaners will do the same thing. The marketing is there to make it appear otherwise and that you are getting something extra in that magical bottle you paid a lot for.

Marco
01-01-2010, 18:16
I wouldn't disagree with that summary, Paul. However, perhaps the AI Chris uses genuinely brings something else to the party to justify its cost? Personally, I would never pooh-pooh its efficacy without trying it first for myself :)

Marco.

The Grand Wazoo
01-01-2010, 18:53
You can see that the MRA on some vinyl records is applied more liberally than others. The ones that are really coated in it don't allow the cleaning liquid to be spread evenly over the vinyl. You brush it on evenly & then you can see parts of the record repelling the liquid, so you end up with a sort of latticework of tiny puddles, rather than an even wetting. No matter how much you brush, the result is the same. These need several goes with a much stronger solution to get them truly clean.

Marco
01-01-2010, 19:37
Yep, I can totally relate to that experience too, as I find the exact same thing when I clean records on my RCM :)

Basically, whatever media you use to play music on (and its playback ancillaries), for best performance, can never be too clean or free from static!

Marco.

Themis
01-01-2010, 21:35
Except tapes...:eyebrows:

Marco
01-01-2010, 21:43
Get tape dirty and see what happens! :eyebrows:

Marco.

Themis
01-01-2010, 21:48
Get tape dirty and see what happens! :eyebrows:

Marco.
No chance, I clean them every day in the bath ! :lol:

tfarney
01-01-2010, 22:23
No, CDs are not burned. CDs are stamped just like LPs.

The data pits are stamped into the polycarbonate disc using a metal stamper which also moulds the disc (just like a vinyl LP). The stamped side of the disc is then coated with a fine layer of aluminium by vapour deposition. The aluminium layer is then covered with an acrylic layer (spin coated I believe) and the label is printed or silk screened onto the acrylic.

In a perfect world all CDs would be cleaned and polished before they leave the factory but just like with vinyl, this is not done (vinly records also tend to come covered in mould release agent).

In a perfect world all CDs would also be run through a Nespa finaliser.

Sadly we don't live in a perfect world. We live in a greedy one :(

Thanks Chris, that's great information.

Tim

Barry
25-07-2014, 20:42
From the Grave

Wudge
29-09-2014, 00:11
I once read that when wiping a disc you should do it radially rather than in a circular manner. Does anyone know if this is true or a myth, and if its true what the logic is?

Barry
29-09-2014, 11:02
I once read that when wiping a disc you should do it radially rather than in a circular manner. Does anyone know if this is true or a myth, and if its true what the logic is?

The disc spins and is read by the laser, so if the disc is wiped in a circular manner with a less than clean cloth, it is quite possible that it will leave circular scratches on the disc. Since the scratches are in the same sense as the track and the path of signal information, the error correction mechanism will not work properly.

If the disc is wiped using radial strokes, any scratches that might occur will be across the track of the spinning disc, so will cause minimum interruption to the signal and allow the error compensation mechanism to work.

So, only use a clean lint-free cloth and wipe the disc using light radial strokes.

The Black Adder
29-09-2014, 11:06
I once read that when wiping a disc you should do it radially rather than in a circular manner. Does anyone know if this is true or a myth, and if its true what the logic is?

I've always wiped them from the center outwards with a lint free cloth. I remember reading about cd's in the early 80's which suggested this. But I seem to remember Tomorrows World spreading one with Jam that worked perfectly... lol

I'm showing my age now... :)

....and the laser record player... blimey, where did that go? Wonder if that actually sounded good.

Macca
29-09-2014, 11:18
....and the laser record player... blimey, where did that go? Wonder if that actually sounded good.

I've got the 2 part HFW review. It had two main problems, firstly it read every bit of crud on the disc, including stuff that a stylus would usually push aside so the records had to be absolutely minty clean and undamaged/unworn. Second it was bass-shy, possibly due to lack of acoustic feedback. A further, minor disadvantage was that it cost 14K. I say 'was' I have no idea if they still make them.

The Black Adder
29-09-2014, 11:32
I've got the 2 part HFW review. It had two main problems, firstly it read every bit of crud on the disc, including stuff that a stylus would usually push aside so the records had to be absolutely minty clean and undamaged/unworn. Second it was bass-shy, possibly due to lack of acoustic feedback. A further, minor disadvantage was that it cost 14K. I say 'was' I have no idea if they still make them.

lol... of course, 'dirt'... That's a shame, I Suppose nobody has made one since. Bet they could do some magic trickery these days to make them better though.

anyway, thread drift... apologies. (might be worth a thread just about this)