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I was thinking about the fact that in the last years I have never seen CDs and DVDs supporting writing/reading speeds higher than 52X and 16X, respectively.

Is this a commercial choice (i.e. manufacturers don't care about optical discs anymore and focus more on flash memories and SSD drives) or a technical limitation (i.e. optical drives cannot support higher writing and reading speeds)?

8 Answers 8

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It's mostly a technical limitation. Put simply, if you spin the disk too fast it starts to become unstable and wobble around or even start to come apart under the sheer stress. At best this means read/write errors - and at worse means the possibility of it coming loose and causing damage.

At 52x speed, the disk is spinning at around 24000 RPM - at around 27000 RPM the disk would start to crack.

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    They could modify the disk in theory to suppor higher RPMs the problem of course is that they would create a new standard for a media that is slowly being discontinued. The simple fact is Blu-ray is the future, and most of the manufactures know that, so why waste money making a CD or DVD support faster burn times. You can already burn a double layer DVD in a few minutes.
    – Ramhound
    Commented Feb 20, 2013 at 12:08
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    Yup, infact DVDs can spin faster than CDs before breaking for this very reason. Blu-rays however spin slower because the data density is much higher. If the data is more tightly packed, you don't need to spin the disk as fast to read data at the same rate.
    – PhonicUK
    Commented Feb 20, 2013 at 12:19
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    The speeds of Blu-ray media will only get faster as the data density is increased. Eventually there will be a question on this website in 2023 that asks "Will there ever be faster Blu-ray disks and writers?" :-)
    – Ramhound
    Commented Feb 20, 2013 at 12:21
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    @Ramhound Nah in 2023 it will be "Why does it still take 10 minutes to transfer a new language via BrainLink?"
    – PhonicUK
    Commented Feb 20, 2013 at 13:43
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    Forget about BrainLink its all about BrainLink 2.0
    – Ramhound
    Commented Feb 20, 2013 at 13:49
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KenWood has played with CD-ROMs that use multiple lasers to read several places on the disc at once and then re-compose them into a single stream in firmware. They call this technology TrueX. You're able to read data faster at the same spin rate, but you need to use a more powerful laser (since it's being split), which requires more power and results in more heat.

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About a decade ago there were CD drives that used multiple laser beams to read 7 tracks at once for higher performance without having to spin the disk extremely fast. However they were expensive and apparently had reliability problems as well.

It's also worth noting that it isn't just a question of structural integrity of the disk at high RPMs, but also of noise.

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15 years back...

"Will there ever be floppy disk with capacity more than 1.44 M?"

"Will there ever be floppy disk with higher read/write speeds?"

(For those who incase don't know, what floppy is: http://en.wikipedia.org/wiki/Floppy_disk)

Today, we don't care for an answer to above questions, simply for the fact that 'flop'pies have flopped.

Now, even CD-DVDs are approaching a similar state & have been replaced by Flash drives & Memory Cards. And in years to come, mechanical Hard Disks will follow the suite & will be completely replaced by SSDs.

The root lies in storage technologies involving mechanical movement/rotation are slow, error prone, require more power, make more noise, generate more heat & will be replaced by their non-mechanical counterparts & technology by next decade.

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I personally doubt there will be a lot of work done in making the spin rate or RPMs faster on CDs or DVDs because the main reason to make them faster would be to be able to read or write the data to the disc then store it somewhere or perhaps send it to someone. However with the internet and network speeds getting faster, along with other technologies that allow us to share files to people of our choice, there is little need to make the discs spin faster as other technologies are already much faster than CD's or DVDs in terms of read and write speed.

If you look at the cost of a 2TB WD passport drive they cost around $100 and they fit in the palm of your hand, that beats discs any day for storage and speed, along with durability and portability.

I do think that having a CD or DVD available has its merits, like when you need an OS CD to fix an installation of an operating system, but for sending data there are faster and cheaper ways of doing that these days.

I just thought I would put my two cents in, hope I didn't upset anyone with this comment Cheers

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Say, at 52x speed, the disk is spinning at around 24000 RPM The diameter of a cd is 11.5 cm Then the perimeter of a cd is 11.5 x pi = 36.13 cm

The edge of the cd rotates at 24000 rotations per minute, so the speed of the edge of the cd is 36.13 x 24000 x 60 = 52024763 cm/hr

This is 520247.63 m/hr = 520 km/hr = 323 mph

So how much faster do you want it to go?

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I'm not enough of a technical expert to say this with extreme conviction, but I'm convinced that it's purely an economic issue. Yes, there are technical issues (several previous answers mention some really nasty ones) but technical issues have a way of disappearing when somebody has an economic incentive to make them go away.

And there's simply no economic incentive to develop faster optical drives. Optical media is no longer a primary means of getting data into computers. I can't remember the last time I used a CD or DVD to install software. It's easier to download it. On the rare occasions I need removable media (transferring network drivers to a system with a fresh OS install; using bootable media to install an OS) thumb drives usually make more sense.

My main laptop has a DVD drive that I've only ever used to watch movies — and it's plenty fast for that.

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  • Sure, technical limitations do tend to go away when there is enough money at stake. In this case I don't think that's the case, though--there's not that much advantage to faster transfer speeds. That would normally only be much of an issue to the sort of people that post here--and we have better options for throwing around big piles of data anyway. Commented Feb 27, 2013 at 2:57
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    @LorenPechtel How is that different from what I said? Commented Feb 27, 2013 at 6:33
  • There is SOME economic incentive--the casual user. It's just there's not ENOUGH. Commented Feb 27, 2013 at 21:12
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I've seen many CD drives reading at 56x. So for the 52x speed, the answer is yes. But no more higher speed would be available

That's the theoretical speed and it's not easy to reach that value. Speed is highest at the edge of the disc, so you'll only see that maximum speed when reading a full disc at the end

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  • This isn't much of an answer. If the links go dead, is your answer worth much more than a comment?
    – studiohack
    Commented Sep 27, 2013 at 1:09
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    @studiohack: What I said is that 56x CD drives exist. Just provide the links for some example. If they go dead, there are still hundreds of them on google
    – phuclv
    Commented Sep 27, 2013 at 1:16

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