pq masters

[josha]

why is it advised that one doesn't play the final pq master c.d. too many times?

[acorneau]

Originally Posted by josha

why is it advised that one doesn't play the final pq master c.d. too many times?

I don't think there is anything wrong with just playing a CD-DA over and over again. It's the higher chance of fingerprints, scratches, smudges, dust (etc.) from all the handling.tutt

[lm66]

Originally Posted by acorneau

I don't think there is anything wrong with just playing a CD-DA over and over again. It's the higher chance of fingerprints, scratches, smudges, dust (etc.) from all the handling.tutt

+1

That's why the best way (IMHO) is to burn 1 pre-master CD (QC verified and then sealed in his box for remaining untouched until it comes to the replication's plant) and 1 reference CD for the customer (which may be submit to any kind of torture without any consequences...).

[Jerry Tubb]

... and if you archive the clients' audio files, it'll still exist, even if the master and ref gets lost or destroyed.

jT

[twwalsh]

Originally Posted by lm66

+1

That's why the best way (IMHO) is to burn 1 pre-master CD (QC verified and then sealed in his box for remaining untouched until it comes to the replication's plant) and 1 reference CD for the customer (which may be submit to any kind of torture without any consequences...).

i advise the client to listen to the production master exactly once before sending it for replication. one last step of QC and it sets the client's mind at ease.

[fenderbender.]

Originally Posted by josha

why is it advised that one doesn't play the final pq master c.d. too many times?

It's just unnecessary. We listen to the disc for you. You have the reference disc that you approved. It's the same thing as the master, but potentially with more errors and other problems. Are you going to run it through a Clover before you send it to the factory? No one likes a failed master. Mastering is just as much about quality control as it is about audio "sweetening". We need to be the next-to-last-step in the production process if you're going to trust us to make sure that what's duplicated is what you intended. You shouldn't need to worry about the mastering house screwing up your CD-DA duplication disc!

[MASSIVE Master]

Originally Posted by twwalsh

i advise the client to listen to the production master exactly once before sending it for replication. one last step of QC and it sets the client's mind at ease.

I agree (as I always listened to masters before sending them off myself when work was being done for me). I advise the client to carefully put the disc into a quality player (not a car unit that "eats" the disc, but something with a tray at least). Skip through it once listening to all the start points, then listen to it once all the way through.

I also agree that it's not a necessity for the most part - Still, I've never sent a disc out for replication without auditioning it myself. I wouldn't be offended in the least if the client wants to hear it for him/herself.

[Roland]

Originally Posted by acorneau

I don't think there is anything wrong with just playing a CD-DA over and over again. It's the higher chance of fingerprints, scratches, smudges, dust (etc.) from all the handling.tutt

That's wy we supply our customers with a listening copy for QC and we use DDP folders for the pressing, if it doesn't fail during glass mastering we know that the replicated copies will sound as good as the original. CD-DA has always had the problem of no parity check hence there is always a risk of contamination that can find it's way onto the final product. Being that this information has been well documented for a number of years I am amazed that people still go te CD-DA route. I've seen the lengths to which people go in order to obtain particular makes of disc's that have reputations for low error counts, plextor drives and the assocciated software in order to check for C1 C2 BLER. DDP it, and as long as you accurately document to the factory what you are sending them (i.e. Label it clearly and document it on your order form) you can sleep easy in the knowledge you have supplied the best possible master for replication.

Regards to all


Roland

[Thor]

Yet another reason to deliver a DDP.

Give the client a ref cut from the DDP to listen to, deliver the DDP to the plant.

Thor

Originally Posted by lm66

+1

That's why the best way (IMHO) is to burn 1 pre-master CD (QC verified and then sealed in his box for remaining untouched until it comes to the replication's plant) and 1 reference CD for the customer (which may be submit to any kind of torture without any consequences...).

[twwalsh]

Originally Posted by Roland

That's wy we supply our customers with a listening copy for QC and we use DDP folders for the pressing, if it doesn't fail during glass mastering we know that the replicated copies will sound as good as the original. CD-DA has always had the problem of no parity check hence there is always a risk of contamination that can find it's way onto the final product. Being that this information has been well documented for a number of years I am amazed that people still go te CD-DA route. I've seen the lengths to which people go in order to obtain particular makes of disc's that have reputations for low error counts, plextor drives and the assocciated software in order to check for C1 C2 BLER. DDP it, and as long as you accurately document to the factory what you are sending them (i.e. Label it clearly and document it on your order form) you can sleep easy in the knowledge you have supplied the best possible master for replication.

Regards to all


Roland

fair enough. but in the case of CDR premasters...

the QC ref master should be exactly the same content, of course. but what if a mistake was made and the production master is different?

as a client, i'd be less concerned about errors and more concerned about the mastering house accidentally sending me the wrong cdr...the client should be sure that the right record is going off for replication...stranger things have happened than someone popping the wrong disc in a sleeve or jewel case...

[lm66]

I do QC of the premaster CD (listening from beginning to end, checking fades at loud volume, checking indexs are really the desired ones and fully functionnal + Plextools report) with the customer when he's available.
Except for the rare FTP jobs I have of course.

I really need he valids the job before sending it to the plant.

On PQ's list I give my contact to the plant. In case of any problem I prefer they call me directly.

Then I burn the reference CD, the customer will make the QC himself...

Of course I keep a backup of all the job on HD until the "real" CD is here.

I don't have any way to deliver DDP and I understand it's a better media than CD for premasters.
But the price of the necessary DDP soft working with Wavelab is so high...

[fenderbender.]

Most factories don't accept DDP's, at least not without a fight. Discmakers, for example, always wants CD-DA dupe. masters and not DDP's.

The exact same image that was used to burn the client-approved reference disc should be used to burn the production master. The client must always approve from a reference disc that they've listened to. The master is listened to by the engineer or an assistant and the client is instructed not to play or handle the master disc. This is the policy of most professional mastering houses. Call Grundman, Gateway, Sterling and others and see what they say!

If you think that your ME is capable of burning the wrong duplication master, what else might they screw up? And, you're going to somehow double-check their work by listening through a pair of headphones? How likely is it that there would be a problem with the markers/sequence and not with the audio? Right about the time that they accidentally moved the track 4 start marker they also changed the gain on the software brickwall limiter. Do you think that Bono and Kanye West sit around and listen to their masters before they go to the factory? Or their agents, or an assistant at the label? You're giving away trust by telling the client that they need to listen to their master!

[Brad Blackwood]

Originally Posted by fenderbender.

Most factories don't accept DDP's, at least not without a fight. Discmakers, for example, always wants CD-DA dupe. masters and not DDP's.

The exact same image that was used to burn the client-approved reference disc should be used to burn the production master. The client must always approve from a reference disc that they've listened to. The master is listened to by the engineer or an assistant and the client is instructed not to play or handle the master disc. This is the policy of most professional mastering houses. Call Grundman, Gateway, Sterling and others and see what they say!

If you think that your ME is capable of burning the wrong duplication master, what else might they screw up? And, you're going to somehow double-check their work by listening through a pair of headphones? How likely is it that there would be a problem with the markers/sequence and not with the audio? Right about the time that they accidentally moved the track 4 start marker they also changed the gain on the software brickwall limiter. Do you think that Bono and Kanye West sit around and listen to their masters before they go to the factory? Or their agents, or an assistant at the label? You're giving away trust by telling the client that they need to listen to their master!

AMEN!

[Roland]

Originally Posted by fenderbender.

Most factories don't accept DDP's, at least not without a fight. Discmakers, for example, always wants CD-DA dupe. masters and not DDP's.

I can't believe that, because it doesn't make sense. I have had masters duplicated in at least 10 different plant's and I haven't come across one that doesn't accept them. With around 4,000 different masters to my name over the last 18 years I have never had a faulty pressing that was down too me or my work. Using CD-DA when there is a more robust format out there is crazy. I produce DDP folders because I am a professional, I have pro quality equipment capable of generating DDP folders and it is the most robust format available for CD production. If a client was to insist on me producing a CD-DA (it has never happened yet!) I would do so only at their own risk because you can't guarantee it, dust, a scratch, fingerprints, some other form of contamination, you can't prove who was responsible, you, you're client, the intern at the factory drops it on the floor and doesn't tell anyone (he doesn't want a bollocking). If Discmakers won't use it, use another plant.

Regards


Roland

[Brad Blackwood]

Originally Posted by Roland

I can't believe that, because it doesn't make sense. I have had masters duplicated in at least 10 different plant's and I haven't come across one that doesn't accept them. With around 4,000 different masters to my name over the last 18 years I have never had a faulty pressing that was down too me or my work. Using CD-DA when there is a more robust format out there is crazy. I produce DDP folders because I am a professional, I have pro quality equipment capable of generating DDP folders and it is the most robust format available for CD production. If a client was to insist on me producing a CD-DA (it has never happened yet!) I would do so only at their own risk because you can't guarantee it, dust, a scratch, fingerprints, some other form of contamination, you can't prove who was responsible, you, you're client, the intern at the factory drops it on the floor and doesn't tell anyone (he doesn't want a bollocking). If Discmakers won't use it, use another plant.

What is this, a steak swinging contest? I've cut a few masters in my time, cut a large percentage as CDDA and have had ONE plant rejection, which the plant admitted was their fault.

DDP's are great, I cut them when they are requested, but to act as if CDDA is inferior is laughable, imo, considering probably 90%+ of all masters cut today are from CDDA.

[twwalsh]

Originally Posted by fenderbender.

Most factories don't accept DDP's, at least not without a fight. Discmakers, for example, always wants CD-DA dupe. masters and not DDP's.

The exact same image that was used to burn the client-approved reference disc should be used to burn the production master. The client must always approve from a reference disc that they've listened to. The master is listened to by the engineer or an assistant and the client is instructed not to play or handle the master disc. This is the policy of most professional mastering houses. Call Grundman, Gateway, Sterling and others and see what they say!

If you think that your ME is capable of burning the wrong duplication master, what else might they screw up? And, you're going to somehow double-check their work by listening through a pair of headphones? How likely is it that there would be a problem with the markers/sequence and not with the audio? Right about the time that they accidentally moved the track 4 start marker they also changed the gain on the software brickwall limiter. Do you think that Bono and Kanye West sit around and listen to their masters before they go to the factory? Or their agents, or an assistant at the label? You're giving away trust by telling the client that they need to listen to their master!

this is some hard-line rhetoric. tell kanye i said hi!

[lm66]

Do you think that Bono and Kanye West sit around and listen to their masters before they go to the factory? Or their agents, or an assistant at the label? You're giving away trust by telling the client that they need to listen to their master!

If this comment is adressed to my post, I'm sorry if I've been misunderstood or if I misunderstand (due to my poor english...).

I don't master any Bono's prod, only demos and sometimes unknown commercial prods.
This may explain my way to work.
I only want to be sure the customer (I don't care if he's the artist, the "artistical" producer or the cousin of anyone playing in the band), is happy and approves the final job.
I may make some mistakes sometimes...

But I understand real MEs never make mistakes.

[Roland]

Originally Posted by Brad Blackwood

What is this, a steak swinging contest? I've cut a few masters in my time, cut a large percentage as CDDA and have had ONE plant rejection, which the plant admitted was their fault.

DDP's are great, I cut them when they are requested, but to act as if CDDA is inferior is laughable, imo, considering probably 90%+ of all masters cut today are from CDDA.

Hi Brad, I'm not argueing your credentials, you and I have both posted on this forum for a good number of years and I'm not about to question the quality of your work. However, as you say DDP's are great, and with the added bonus of a full parity check the only errors that are hitting the disc are those incurred as a result of glassing, producing the stamper and pressing, even if your CD-DA is really low on error count when tested, there will still be more errors on the final discs. I know in real terms this is unlikely to be a problem if you go through the process (as I am sure you do), but not everyone is as fastidious or as knowlegeable as you are and having heard the results of pressings that have gone wrong it strikes me that using a system that eliminates a variable from the process ultimately makes good sense, well it does for me anyway.

Regards


Roland

[Brad Blackwood]

Originally Posted by Roland

even if your CD-DA is really low on error count when tested, there will still be more errors on the final discs.

That's not true - an audio disc with no CU errors will yield a data stream that is EXACTLY like what's in your DAW.

Frankly, most mastering engineers supply what the client asks for. I've occasionally recommended DDP images (for overseas clients) but while the DDP is more robust, a good audio disc yields exactly the same master...

[Thor]

Steak swinging? What about Fish slinging? Or Slime throwing?

Whatever makes you happy . I'd prefer beer guzzling myself .

I don't know how things are there in the US, but here most of the 'serious' plants take (and prefer) DDP. Often brokers have no idea what the plant wants or what formats they accept and request a CDDA by default, in my experience. There aren't a whole lot of pressing plants here, so it's pretty easy to know what format to deliver (one takes CDDA only, all others accept DDP).

Like you, I think both are fine if properly treated and QC'ed, I think part of the touted advantage with DDP is slightly better error correction (being written to disc as data, not as audio). One advantage in my eyes is that the client isn't going to break the seal to have a listen with their friends before sending it off for pressing. Even with a ref and CDDA master, one guy in the band might take off with the ref and someone else gets the master and just wants to have a quick listen... tutt

Additionally (but marginally), certain types of adjustments are easier/faster when working with DDP's. I.e. if the audio is great but the client wants a start mark nudged a tad, this is done in 2 seconds with a DDP - adjust to taste in the EDL, dump the new PQ info to the existing DDP fileset and you're golden. With CDDA you have to cut an entire new disc, QC it, etc.


Cheers,
Thor
--
Sonovo mastering
www.sonovo.no

Originally Posted by Brad Blackwood

What is this, a steak swinging contest? I've cut a few masters in my time, cut a large percentage as CDDA and have had ONE plant rejection, which the plant admitted was their fault.

DDP's are great, I cut them when they are requested, but to act as if CDDA is inferior is laughable, imo, considering probably 90%+ of all masters cut today are from CDDA.

[Roland]

Originally Posted by Brad Blackwood

That's not true - an audio disc with no CU errors will yield a data stream that is EXACTLY like what's in your DAW.

Frankly, most mastering engineers supply what the client asks for. I've occasionally recommended DDP images (for overseas clients) but while the DDP is more robust, a good audio disc yields exactly the same master...

Somebody takes one of your good CD-DA's out of the packet, sticks a dirty great thumbprint on it, it is stuffed into a drive at the plant. You checked it and it was fine, it's performance is now questionable, almost certainly not as good as it was when you tested it. Add into the equation that many brokers out there tell a client to send in their CD-DA and literally pass it on too the plant. That's great if they were sensible and paid you to master it and produce a final master on a quality disc, checked by you for bler. More often than not it was some cheap, bulk CDR run out either from a small local/home studio on a standard computer drive, taken home by a member of the band to have a listen too, possibly copied, then sent to one of the hundreds of brokers out there, who because prices are so ludicrously low, simply repacks it with an order form and sends it to XYZ pressings. Of course DDP doesn't guard against this, however I PQ a clients disc, run off a test copy which my customer can listen too and approve, creat a DVD folder that takes about 20 seconds, burn that to a CDR/DVD (I don't have to be fussy about the disc make), and when the disc has been written and verified I am totally safe in the knowledge that it's at least as good as the test disc. Bearing in mind that I understand Plextor have withdrawn from the optical drive market, testing options are going to be worse for CD-DA unless you want to stomp up for a Datarius system or equivelant. I use DDP for the simple reason if it goes wrong, it will flag the error at the plant if it doesn't the fault must have occured during production, then it's down to the plant to put it right.

Regards



Roland

[Brad Blackwood]

Originally Posted by Roland

Somebody takes one of your good CD-DA's out of the packet, sticks a dirty great thumbprint on it, it is stuffed into a drive at the plant. You checked it and it was fine, it's performance is now questionable, almost certainly not as good as it was when you tested it.

Again, it doesn't matter! If there are no CU's, the data will be reconstructed 100% accurately!

I understand the benefits of DDP, I've been cutting them for almost 10 years now. But when someone says "I produce DDP folders because I am a professional, I have pro quality equipment capable of generating DDP folders", it seems like steak-swinging to me. I prefer cutting DDPs, but to act as if it's the mastering engineer's prerogative to cut whatever they wish, or to send it to whatever plant they decide to ("If Discmakers won't use it, use another plant.") makes me think we're in two different worlds...

[Roland]

Originally Posted by Brad Blackwood

Again, it doesn't matter! If there are no CU's, the data will be reconstructed 100% accurately!

I understand the benefits of DDP, I've been cutting them for almost 10 years now. But when someone says "I produce DDP folders because I am a professional, I have pro quality equipment capable of generating DDP folders", it seems like steak-swinging to me. I prefer cutting DDPs, but to act as if it's the mastering engineer's prerogative to cut whatever they wish, or to send it to whatever plant they decide to ("If Discmakers won't use it, use another plant.") makes me think we're in two different worlds...

Brad, call it what you like. What I mean is that I have equipment capable of producing DDP folders (as do you) which differentiates between someone burning a disc off on a copy of Nero or alike. When I started making CD masters for clients I used DDP on Exabyte because it was reliable. At that time I don't believe there was much in the way to test CD-DA masters. When exabyte all but died a death I swapped to using DDP folders. I can write my image file from Pyramix, run off a CDR copy for my client to check, burn the DDP folder to a disc and forget about it. I don't have to run checks for bler or CU's, I don't have to source Taiyo Yuden discs, I don't need a Plextor drive and software for disc error checking. It is my understanding that any plant using Eclipse sytems can cope with DDP folders and my experience that even plants asking for CD-DA when questioned will admit to being able to accept DDP folders.

I have heard of clients who have sent CD-DA to plants recieved the discs back found audible faults/degradation that were not on the original. On complaining the factory test the replicated disc which of course measure within manufacturers tolerence and then test the original supplied master which displays unacceptably high error rates. Your supplied master was outside of spec, your fault, you pay again. It may be that plants now check disc's prior to manufacture (indeed I PQ'd a disc for a brokers client about 3-4 months ago that their plant rejected), but I was told albeit several years ago by the technical manager for KDG Austria (a division of the same company that owns Datarius) transfers from CD-DA to glass are bit for bit errors and all and that problems occurred where these along with the errors introduced by the nature of it being a plastic stamping operation accumalted beyond the ability of a CD player to error correct. Of course I wouldn't be at all surprised if newer glass mastering systems are able to interpolate errors, but as all things in all industries not all companies are running the latest kit, particularly with the huge amount of investment glass mastering requires and the relatively low margins in manufacture these days. It is possible that your experiences differ on your side of the pond, however I have seen this subject beaten to death on Glenn's mastering forum, so obviously a lot of mastering engineers consider producing CD-DA's (obtaining good disc's, plextor drives, etc) and testing them an issue. I use DDP folders, I don't have any issues, no risks, no comeback and because I don't need to check them or listen to them it's much more cost effective for both me and my customers. Of course YMMV.

Regards


Roland

[Masterer]

Both approaches are viable and have advantages or disadvantages.

The only time you'll ever have a conversation about which plant to use is when the clients are VERY independent [usually releasing the record ontheir own]. Major labels and bigger indies won't ask you where to send a master. They will tell you where to send it - and what to send.

'Till recently it wasn't uncommon for us to send Japanese clients masters on 1630 U-matic tapes. Go figure - they invent the shit but...... anyway, maybe I'm in the minority but when I'm dealing with an independent client that is trying to decide where and how the master is sent I encourage them to take a CD master and I encourage them to listen to that CD master. Obviously we have a conversation about the care and handling of the master but this gives the client a chance to quality control the actual production master - NOT a copy of it. The client gets the last crack at catching anything that may have gone wrong with the master - or anything I may have missed when I QC'd the master.

DDP's are very convenient and reliable but if the clints preffered plant accepts only or prefers CD's I see no reason to talk them out of using that plant.

[Thor]

Hi Chris,

I think you and Brad (and Roland, he just hasn't said it) have made the important point - what's delivered is up to what the client needs/requests. They (or others) decide where to press and how, not us.

That said, I'm a bit curious as to how plants operate in the US. Are most places set up to accept DDP's, or is CDDA a common (even majority) delivery format there? I was under the impression that most plants (as well as internal master archives used by the majors) had standardized on DDP. Every Eclipse used to be set up to read DDP on Exebyte, reading the same data from a CD/DVD can't be much of a jump, can it?

1630 Umatic?!? You're kidding, right? I guess they really know how to get the most out of their investments. Those units must be ancient by now. Amazing their still running.

You are in the minority, you work at Sterling! But, you knew that already. I give the client a ref cut from the DDP image (and nulled to verify an exact copy) to listen to. Even when I deliver CDDA masters I do the same. The master is sealed and given to the client or sent directly to their choice of broker/pressing plant/whatever.

Cheers,
Thor

Originally Posted by Masterer

Both approaches are viable and have advantages or disadvantages.

The only time you'll ever have a conversation about which plant to use is when the clients are VERY independent [usually releasing the record ontheir own]. Major labels and bigger indies won't ask you where to send a master. They will tell you where to send it - and what to send.

'Till recently it wasn't uncommon for us to send Japanese clients masters on 1630 U-matic tapes. Go figure - they invent the shit but...... anyway, maybe I'm in the minority but when I'm dealing with an independent client that is trying to decide where and how the master is sent I encourage them to take a CD master and I encourage them to listen to that CD master. Obviously we have a conversation about the care and handling of the master but this gives the client a chance to quality control the actual production master - NOT a copy of it. The client gets the last crack at catching anything that may have gone wrong with the master - or anything I may have missed when I QC'd the master.

DDP's are very convenient and reliable but if the clints preffered plant accepts only or prefers CD's I see no reason to talk them out of using that plant.

[lucey]

Originally Posted by Masterer

maybe I'm in the minority but when I'm dealing with an independent client that is trying to decide where and how the master is sent I encourage them to take a CD master and I encourage them to listen to that CD master. Obviously we have a conversation about the care and handling of the master but this gives the client a chance to quality control the actual production master - NOT a copy of it. The client gets the last crack at catching anything that may have gone wrong with the master - or anything I may have missed when I QC'd the master.

+1

My self-releasing artists listen once, then send it off, saving them time/money and giving them a final shot at both QC and any tweaks. They're often rushing and could use another listening pass now vs. 3 months later, wishing it was different from a better head space. They get a second CD for their short term needs.

For labels I do the QC. Ship to the duplicator, ship to them.

[master commander]

I've instituted a new policy this year that seems to work. All masters must be picked up in person by naked dancing ladies.

[fenderbender.]

Originally Posted by Roland

...It may be that plants now check disc's prior to manufacture...It is possible that your experiences differ on your side of the pond, however I have seen this subject beaten to death on Glenn's mastering forum, so obviously a lot of mastering engineers consider producing CD-DA's (obtaining good disc's, plextor drives, etc) and testing them an issue....

Yes, QC/testing is an issue, but CD-DA masters can be sent without errors if done properly. In my experience most factories prefer CD-DA discs. This is probably different for everyone depending on location and a number of other things. Usually, once the factory receives the disc they extract the audio using Eclipse ImageCopy (most likely being converted to a DDP image!). Any C1/C2 errors are corrected during this extraction. The image is verified against the disc using Eclipse ImageAnalysis. If all is well the LBR system will pull the image across the network and go from there.

The point is - an audio CD can be a good medium for delivery if done properly. As long as you don't screw something up while making the part you can just put it in an envelope and give it to the client and say "don't open this. give it to your duplicator" and have no problems(as long as the disc surface stays clean, hence the "don't open this" discussion). We make DDP's when clients ask for them, but otherwise CD-DA continues to work fine while providing a familiar and reasonably-reliable-if-done-properly format for our customers. As long as the ME is careful in what they do it shouldn't matter which format, DDP or CD-DA.

[Cellotron]

Originally Posted by Roland

I have heard of clients who have sent CD-DA to plants recieved the discs back found audible faults/degradation that were not on the original.

MUCH more likely due to either this effect: Why We Believe - OR the client using a consumer grade playback transport with a DAC which does not reclock or has a poor clock - and the disc having poor pit geometry due to problems during the developing of the glass master or the electroplating of the nickel stamper - or problems at the press in molding or metallizing - than anything to do with the transfer from the provided master. Of course most ME's don't have plant side experience so they just point the blame at the one thing they think they have a grasp on - the transfer - instead of trying to investigate what really happens during optical disc manufacturing.

On complaining the factory test the replicated disc which of course measure within manufacturers tolerence and then test the original supplied master which displays unacceptably high error rates. Your supplied master was outside of spec, your fault, you pay again.

Huh? When the heck has this happened at a reputeable plant in the last 10 years? Every plant worthy of the 35 some cents a disc I know of PRETESTS EVERY single CD-R master received. If the test shows bad subcodes, out of book spec TOC, or comes back with even a single E32 (aka "CU" or "uncorrectable error") a decent plant will reject the master prior to any further work and either ask for a new one or offer to "repair" it. Most plants also reject masters which has a sector that averages more than 200 C1's per second or that has a sector with a number of C2's.

The policy of pre-testing is not just designed to save clients aggravation - it's primarily designed to save the company by not wasting time materials, labor and press time or creating liability and ill will by making defective product.

It may be that plants now check disc's prior to manufacture (indeed I PQ'd a disc for a brokers client about 3-4 months ago that their plant rejected),

If they have any semblance of their own interests, let alone their clients, as even a minor consideration - THEY DO - see above.

but I was told albeit several years ago by the technical manager for KDG Austria (a division of the same company that owns Datarius) transfers from CD-DA to glass are bit for bit errors and all and that problems occurred where these along with the errors introduced by the nature of it being a plastic stamping operation accumalted beyond the ability of a CD player to error correct.

The tech manager either provided you that info a good many years ago - or people should write down the name of that plant as one to avoid.

At this point (and in fact for a number of years) Eclipse allows for highly "secure" image extraction - where correctable errors are indeed corrected on read in of the image to a temporary storeage place (usually hard drive) prior to sending the data stream to the LBR.

i.e. - from ImageEncoder
Advanced Read-in
Multiple images can be read-in and analyzed concurrent with mastering. Many image problems such as incorrect postgap, link blocks, subcode problems, and 3rd layer correctable errors are identified and can be easily corrected during the read-in process. This on-the-fly image correction allows for higher yield at mastering.

Of course I wouldn't be at all surprised if newer glass mastering systems are able to interpolate errors,

The only errors that need to be interpolated are CU's! All other errors are completely correctable by heeding the error flag and having the correct data for the sector in question confirmed from redundant sectors.

One of the main points of the pre-test is to reject all masters that have ANY CU's! So - for plants doing secure image extraction - the result is that the extracted image has no errors.

Of course - there are indeed plants that's QC leads a lot to be desired - or that have outdated glass mastering facilities - especially if the client chooses only on price and not on a plants record of quality. BUT again - more issues are more likely to potentially occur during plating the glass master and at pressing than they do at the transfer from CD-R.

Just as background - I'm basing my above statements on my direct experiences as a production manager at a CD replication plant, and from the collected conversations with the head optical disc & glass mastering technicians at Europadisk, where I worked for a number of years.

Anyway - I agree that the parity check and the ability to FTP images makes DDP a potentially powerful tool - but for many plants their work flow has been optimized to deal with CD-R masters.

Best regards,
Steve Berson