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irishcrazy2005
2004-11-19, 11:53 PM
I may just be totally missing something here, but what is a silver pressed CD?

-Phil
pnagel@<hidden>

Five
2004-11-20, 12:00 AM
a cd that's not a cdr. they're Silver, whereas cdrs are gold or blue or something. Silvers are more durable.

For example, a legit cd you get at the store is always a "silver"

I'm sure somebody will have more to add to this...

RainDawg
2004-11-20, 12:28 AM
Basically, a writeable CD, or a CDR, contains a dye that is aligned with a laser to construct the data layer of the CD.

A silver pressed CD actually contains a physically stamped data layer, making it much more durable. It also means that it's an original and has not been through many generations of potentially flawed extracting and re-burning, which is why we prefer to have seeds from original silver pressed CDs seeded if possible.

Take a look at your original discs, and notice how they are silver compared to the green or purple or blue of the dye of your CDR.

If you really want some insane detail on the subject, here's an awesome link to everything you ever wanted to know about audio CDs:
http://www.cdrfaq.org/

wazoo2u
2004-11-20, 12:29 PM
2 biggest differences between CDR's and Stamped Silver CD's are:

1) CDR's Dye Layer is suseptible to deterioration due to exposure to light and because the upper surface is thinner and less durable than silvers.

2) Stamped disks have clearly defined perforations that the laser then reads as 1's & 0's (or pits and lands to be more accurate). Unlike the precise holes created in the stamping process, if you look at the laser burned holes on a CDR through an electron microscope (lemme open my desk draw here and get mine...... ahh.. yes, there they are ;) ), you'll see that they're very ragged and imprecise. This causes errors on decoding, which means that Reed Solomon error correction needs to work much harder to decode an audio disk that you burn on your computer. There is built in error checking when you do data disks, so the laser can go back and re-read sectors if necessary.

Ditto the McFadden FAQ that RainDawg has pointed you to. This document has been carefully tended, and drawn from many sources, but mostly from the pioneering Usenet groups that dealt with burning stuff to disk. It's invaluable knowledge if you need to know this stuff.

irishcrazy2005
2004-11-20, 01:11 PM
if you look at the laser burned holes on a CDR through an electron microscope (lemme open my desk draw here and get mine...... ahh.. yes, there they are ;) )

You joke about that, however I am a chemist and have access to both an electron microscope and a scanning tunneling microscope (which is the main instrument that I use in my research). I could look at the individual atoms of the suface if I wante to, lol! Anyway, I just thought that was rather funny.

-Phil
pnagel@<hidden>

malick
2004-11-21, 12:35 AM
please report back to us in the morning. screen shots would be nice too!

;)

irishcrazy2005
2004-11-21, 01:27 AM
please report back to us in the morning. screen shots would be nice too!

;)

Well our microscope is only equipped to handle samples approx. 1 cm x 1 cm. Therefore I would have to cut up a CD to do it, and I would rather not do that.

-Phil

Karst
2004-11-21, 06:41 AM
One major difference is as well that a silver disc in general comes from a glass master while the CD-R comes from an extracted format that then goes through the process indicated in the cdrfaq.

wazoo2u
2004-11-21, 08:17 AM
You joke about that, however I am a chemist and have access to both an electron microscope and a scanning tunneling microscope (which is the main instrument that I use in my research). I could look at the individual atoms of the suface if I wante to, lol! Anyway, I just thought that was rather funny.

-Phil
pnagel@<hidden>Scans were actually posted on the web, but alas, over time, the site was taken down. I regret that I didn't archive them, because this very subject comes up from time to time.

It is a funny coincidence that you actually have access to one..:lol:

irishcrazy2005
2004-11-21, 05:51 PM
Now that I have this cleared up, I wonder what would be sourced from a silver-pressed CD? Since official releases are not allowed to be spread, I cannot think of other things that might be included.

-Phil

jazzbo
2004-11-21, 06:39 PM
Now that I have this cleared up, I wonder what would be sourced from a silver-pressed CD? Since official releases are not allowed to be spread, I cannot think of other things that might be included.


Before the widespread availability of CDRs, it was not that uncommon for bootleggers to go to places that pressed CD and have limited runs made. The places that did the pressings either cared more about making some money or because of laxer laws in countries like Italy in the 80s legally couldn't be prosecuted so would willingly make bootleg silver CDs.

Even today you can walk into just about any music store and find dubiously licensed material by non-mainsteam artists pressed on silver CDs which presumably would be okay to trade. I would guess that shadier stores and online outfits still actually sell silver CDs of big name bands.

CDRs have made it easier for bootleggers to do 'garage' operations and make their own, but it also has lowered demand, because anyone can make their own CDs -- hence, places like this.

CDRs are even so prevalent I know one record company that (frustratingly) only issues new releases on CDR.

Karst
2004-11-22, 05:50 AM
Most discs are now produced in Eastern Europe. Indeed, the most annoying problem is that these companies now release these discs as cheap CD-R with low quality artwork at the same prices

Gish05
2004-11-22, 06:51 PM
If the media is Taiyo Yuden, Verbatim, or recently made Ritek, I don't think you have to worry about potential skips/gaps/etc. That media is quality. But I realize most CD-R's out there are not, so I understand the rule.

RainDawg
2004-11-22, 06:58 PM
...so I understand the rule.
Which rule is that? If you mean the rule about not seedding CDRx stuff, it has more to do with people not using the right software methods than it does the quality of the CDRs people use. Quite simply, most people do not use verified rips with EAC (or equivalent) and as a conequences the audio's integrity is compromised.

Gish05
2004-11-22, 07:13 PM
Ah, I see.