Duplication vs Replication

[giddyap]

Newbie here. Sorry. Please point me to topic if already answered.
Its my understanding that replication's sole benefit was to make sure people can hear cd in car cd players.
Hasn't car audio technology caught up?
Do cars even have cd players anymore?
What do I risk by having cd's duplicated (cheaper, esp for short runs)???

[Eddy Deegan]

I don't understand the question you're asking. Duplication and replication are the same thing, surely?

Is this a query about mastering such that it sounds good on a car stereo?

[resistorman]

I believe the question is the difference between "burning" discs and stamping them. Sometimes car stereos had issues with the burned ones.

No, car stereos have not caught up, they don't even make them anymore. Those in existence are probably on their last legs. For what it's worth, I never had any problems with burned discs.

Since pro replication requires buying minimum 1000 units, I'd say it's not worth it, unless you live someplace where CDs are still bought.

[giddyap]

Correct, and thanks!
There are many blogs and disc manufacturer's FAQ pages explaining the difference of process. I was quite unaware of it too for many years.
I play live, and I'll tour when my old house, wife, and 5-year-old allow, and merch is always good to have...just not 1000 of them!
CD Baby used to do "download cards" which I thought were great. Someone at a gig would gig you $12 for a download of your 12 songs. Easy enough.
Personally, although I listen digitally I also like a cd because I read lyrics and liner notes. But, I'm on a tangent now.
I am planning on a new record and I plan to make a small run of 300-500 and the cost of duplicating (burning) is much cheaper than have a glass master made and having them duplicated.
So far, from your response, Resistorman, I still plan on doing this.
Gracias.
Anyone else, please?

[Mike Stranks]

When I was organising production of the sort of volumes you envisage, I used a well-regarded one-stop 'burning' house. They offered all the add-ons, such as on-body printing, production of liners etc. at fairly reasonable rates. I never had any issues.

Whether I'd still be considering issuing CDs these days is another matter - but, of course, that's up to you.

BTW, if copyright might be an issue, then PRS/MCPS do a special all-embracing licence for the sort of volumes you're considering.

[The Elf]

I've been aware of this 'duplication'/'replication' difference for a long time. We've even had fans specifically asking about this when buying CDs at gigs! Supposedly one can cause playback problems for some systems.

TBH I can't remember what the difference is now, but we always go the glass master (from DDP) route and no complaints since.

[Aled Hughes]

I don't understand the question you're asking. Duplication and replication are the same thing, surely?

Replication is the 'proper' way of manufacturing commercial CDs. Duplication is essentially what we can do at home with a computer. Duplication is usually cheaper, and usually done in short runs. Replication is the most common way of doing runs of a 1000ish and above.

[MarkOne]

It's not just car stereos. We have a 'professional' Tascam CD player in our church FOH rack that pretty much always ignores burned CDs.

When I self released my debut album, I decided to go down the Replication route, which means I'm happy that the CD will play anywhere, but of course it also means I still have about 300 copies left in my storage unit! (Anyone want one? )

[Hugh Robjohns]

... merch is always good to have...just not 1000 of them!

I've not been involved in CD releases for a while now — all of my recent clients just want files! — but most disc manufacturers seem to duplicate (burn CDs) for less than 500, and replicate (press from a glass master) for more. Some seem to place the duplicate/replicate threshold at 300 and a few even lower.

In the UK replicated discs (with packaging/printing) cost roughly £1000 for 1000 discs, or around £1 each. At 500 replicated discs the price is over £800 as most of the costs are in the setup rather than the output unit, so not much of a saving in practice.

Anyway, if you stamp 1000 discs and sell them for £10 each from your merchandise table or mail order you only need to move a few more than 100 units to filly cover your entire manufacturing costs. Even if you sell at £5 each you still only need to flog 200 units to cover your costs. And if you sell the planned 500 at any price over £2 each you're into profit even if you junk the remainder. So the economics make sense to replicate if you can afford the upfront outlay.

I am planning on a new record and I plan to make a small run of 300-500 and the cost of duplicating (burning) is much cheaper than have a glass master made and having them duplicated.

Duplication is much more reliable than it once was, and modern disc players are a lot more sensitive so won't usually have problems playing them. However, older players tend to lose sensitivity and may well have difficulty... and there are an awful lot of older players about. Do you really want to have to deal with 'faulty returns' of duplicated discs that won't play?

Personally, if you're looking at a run making 500 discs anyway I'd go the glass master replication route, and since the difference in cost isn't that huge I'd seriously consider pressing 1000 discs to allow for generous give-aways to potential clients, radio stations etc without impacting stock for merch sales numbers.

[Aural Reject]

Pretty much what Hugh said.

The only other sometime advantage of duplication is turnaround time....it's usually in the order of a few days delivered (with a similar paper part and onbody spec) vs some weeks for replication (and that has got worse in the UK since Brexit....either longer deliver times or higher prices for UK factories).

[James Perrett]

I'd suggest going down the replication route if you want to look professional. While you can get all kinds of fancy finishes on duplicated CD's - even imitation vinyl - there will always be players that won't work with them.

There is one place that will do replicated CD's in quantities of 100 upwards although one customer of mine had some issues with them and has gone back to his old source who (I think) have a minimum quantity of 300.

[Martin Walker]

I'm sure some companies nowadays will provide glass-master replicated CD in significantly smaller quantities, down to 100 in some cases. Like the others here I think it's worth paying a little extra to avoid any duplicated returns from customers with elderly CD players.

Whoops - replied before reading as far as James' most recent post

The most recent CD I had replicated, we went with a company that offered down to 100 units. We decided to get 200 made, and didn't have any problems with them at all.

[Eddy Deegan]

I am now clear on the difference between duplication and replication. I've no idea why I wouldn't have known but it's clear I've missed the distinction over the years and I'm happy to have been educated on it

Some CD players I've owned have had trouble with burned CDs. My assumption was that this was down to a weaker bounce-back of the laser with a CDR as opposed to the physical pits of a pressed CD.

CDRs are less robust than pressed discs, especially if exposed to sunshine for a bit. The first album I released back in the early '90s was distributed on CDRs but the physical offering of my next will certainly be on silver pressed CDs!

[Hugh Robjohns]

Some CD players I've owned have had trouble with burned CDs. My assumption was that this was down to a weaker bounce-back of the laser with a CDR as opposed to the physical pits of a pressed CD.

Your assumption is correct Eddy.

In a pressed CD the laser is focused to a beam slightly wider than the width of the bump (the stamped pits are sputtered with the reflective layer then sealed with a lacquer and the label printed on top, but the laser shines through from the other side so sees bumps, not pits).

If there's no bump, lots of light gets reflected, so the sensor sees bright. Where there is a bump, its roughly a 1/4 wavelength high, so light reflected from the top of the bump is phase shifted by 1/2 wavelength compared to light reflected from the flat surrounding area. This only works, of course, because the wavelength of the laser light can be determined very precisely, and all the light is phase coherent — all in the same phase to start with.

Consequently, these two reflections from the bump and surrounding land interfere and largely cancel, and so the sensor sees dark. The changing light (no bump) and dark (bump present) reflections as the disc spins and bumps pass under the laser convey the encoded data.

With 'burned' CDs, the data is encoded within a dye layer which the laser light has to get through to reach the reflecting layer, and then get back through a second time to reach the sensor. Consequently, the bright bits aren't anywhere near as bright as on a pressed disc, and so some (especially elderly) players struggle to recognise the difference between bright and dark.... because its more like dim and dark!

And often the problem is compounded in that not only is the encoded data difficult to see, but the servo tracking and focusing mechanisms struggle to follow the track properly too because its like trying to drive down a bendy road in thick fog!

CDRs are less robust than pressed discs, especially if exposed to sunshine for a bit.

Yep, heat and light degrade the dye layer, making everything even darker. It also degrades over time (years or tens of years) too, although some dye chemistries are better than others in that respect.

[Eddy Deegan]

If there's no bump, lots of light gets reflected, so the sensor sees bright. Where there is a bump, its roughly a 1/4 wavelength high, so light reflected from the top of the bump is phase shifted by 1/2 wavelength compared to light reflected from the flat surrounding area. This only works, of course, because the wavelength of the laser light can be determined very precisely, and all the light is phase coherent — all in the same phase to start with.

Consequently, these two reflections from the bump and surrounding land interfere and largely cancel, and so the sensor sees dark. The changing light (no bump) and dark (bump present) reflections as the disc spins and bumps pass under the laser convey the encoded data.

I had to read that a couple of times to really get it but now I do. Very enlightening and thank you for putting it terms that make sense Hugh

[giddyap]

Some CD players I've owned have had trouble with burned CDs. My assumption was that this was down to a weaker bounce-back of the laser with a CDR as opposed to the physical pits of a pressed CD.

Your assumption is correct Eddy.

In a pressed CD the laser is focused to a beam slightly wider than the width of the bump (the stamped pits are sputtered with the reflective layer then sealed with a lacquer and the label printed on top, but the laser shines through from the other side so sees bumps, not pits).

If there's no bump, lots of light gets reflected, so the sensor sees bright. Where there is a bump, its roughly a 1/4 wavelength high, so light reflected from the top of the bump is phase shifted by 1/2 wavelength compared to light reflected from the flat surrounding area. This only works, of course, because the wavelength of the laser light can be determined very precisely, and all the light is phase coherent — all in the same phase to start with.

Consequently, these two reflections from the bump and surrounding land interfere and largely cancel, and so the sensor sees dark. The changing light (no bump) and dark (bump present) reflections as the disc spins and bumps pass under the laser convey the encoded data.

With 'burned' CDs, the data is encoded within a dye layer which the laser light has to get through to reach the reflecting layer, and then get back through a second time to reach the sensor. Consequently, the bright bits aren't anywhere near as bright as on a pressed disc, and so some (especially elderly) players struggle to recognise the difference between bright and dark.... because its more like dim and dark!

And often the problem is compounded in that not only is the encoded data difficult to see, but the servo tracking and focusing mechanisms struggle to follow the track properly too because its like trying to drive down a bendy road in thick fog!

CDRs are less robust than pressed discs, especially if exposed to sunshine for a bit.

Yep, heat and light degrade the dye layer, making everything even darker. It also degrades over time (years or tens of years) too, although some dye chemistries are better than others in that respect.

Let's assume there has been no damage to a CDR. Do you think that a CDR that couldn't be read by someone's 2001 Ford Explorer would still be unreadable in someone's new Tesla? (I\what I'm getting at is car audio technology)

Also, if I have a that 2001 Ford Explorer and it DOES read an undamaged CDR then is it safe to assume that it would also be read in the new Tesla?

[Eddy Deegan]

Let's assume there has been no damage to a CDR. Do you think that a CDR that couldn't be read by someone's 2001 Ford Explorer would still be unreadable in someone's new Tesla? (I\what I'm getting at is car audio technology)

Based on my own experiences albeit without first-hand knowledge of either car systems I would consider that a distinct possibility.

Also, if I have a that 2001 Ford Explorer and it DOES read an undamaged CDR then is it safe to assume that it would also be read in the new Tesla?

I'd say no, it isn't. Each system will have its own quirks when it comes to that sort of thing. There are old systems that will handle CDRs well, there are new ones that won't, there are new systems that will and there are old ones that won't.

When offering a new release on physical CDs, replicated is the way to go because that will work with pretty much everything whereas compatibility with CDRs/duplicated vary more from system to system.

[Mike Stranks]

Let's assume there has been no damage to a CDR. Do you think that a CDR that couldn't be read by someone's 2001 Ford Explorer would still be unreadable in someone's new Tesla? (I\what I'm getting at is car audio technology)

Also, if I have a that 2001 Ford Explorer and it DOES read an undamaged CDR then is it safe to assume that it would also be read in the new Tesla?

Does the Tesla have a CD audio player?

I'm only asking because my last three cars - since 2016 - have not had any means of playing CDs and, as an avid viewer of new car reviews, I haven't seen one for several years. These days it's all Apple Car Play and Android Auto.

Of course, I speak from a UK perspective. Things may be different elsewhere.

(BTW: the high cars/years ratio is because of force of circumstance - two 'duff' cars in succession... ... )

[Hugh Robjohns]

I had to read that a couple of times to really get it but now I do.

Sorry, my inner sub-editor had already gone to sleep when I wrote that, so it probably wasn't as clear as it could have been!

The important points are that the depth of the pressed pits (which become bumps to the reading laser) are design to equal 1/4 wavelength of the infrared laser's frequency.

And a laser is used because it only produces light at one frequency, (and thus one wavelength) with all the light being emitted in the same phase.

So, where there is no bump all the focused spot of laser light reflects from the 'land' of the disc, giving a bright reflection.

Where there is a bump, some of that focused spot covers the bump, and some covers the land around the bump. So some laser light reflects from the top, while some light travels 1/4 wavelength further to the land, and then 1/4 wavelength back before its level again with the top of the bump.

The result is that this 'land light' has travelled a total of 1/2 wavelength further than the 'bump light' putting it 180 degrees out of phase.

Consequently, these two elements combine and cancel out to produce a very dim overall reflection.

The dimensions and precision involved in CDs — and even more so for DVDs and Blurays — are mind boggling small!

I have in my head an analogy that i used when I taught this stuff to BBC engineers, that the tracking servo for a CD has to perform the equivalent of keeping the nose wheel of a jumbo jet aligned directly above the central barrier of a motorway while flying at 700 mph!

Compared to a vinyl record where a bit of rock glued to a telegraph pole is dragged along a ditch by an old tractor, CDs, DVDs and BRs are truly awesome technologies.

[Folderol]

CDRs are plain weird. I've had ones that won't play back on the same drive that they were recorded with, yet are fine on a different drive

Just my 2d