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CDRW Drives Hit 52X Speeds
Sr.Mixalot writes "Just when you think you couldn't burn those shared MP3s any faster, Asus comes out with a 52X Burner. This review at Hot Hardware shows just how fast this drive is versus a Plextor 48X unit. Amazingly, this new breed of CDRW Drives can burn a complete 700MB CD in about 2.5 minutes!"
http://wuarchive.wustl.edu/users/tom/mirrors/cdexp lode/
notable excerpt:
"A 64x drive using CLV would have to rotate the disc with 33,920 rpm when reading an inner track, exposing the hub of the disk to a tangential force of some 45 N/mm2. A point on the periphery of the disc will be moving with 213 metres per second, slightly more than half the speed of sound. Can the disc take that?
The answer is no. A powerful no.
At about 52x, i.e. 27,500 rpm, most manufacturer's CDs blew up in a rain of plastic particles, leaving their marks on the premises. The result was a pile of shimmering plastic chips."
Actually it's more like 40-something times the spin speed of the original CD drives at which CDs shatter. There was an article about this on Slashdot a while ago. I tried searching for it to provide a link, but I couldn't find it.
Many CD drives today are labled as being "52x" as if it means they spin 52x as fast as the earliest 1x caddy cd drives (horrible things).
What they're actually refering to is a 52x (at peak) the transfer rate of the original CD drives, which if I remember rightly, was about ~150kb/s. My "2x" in 1995 could do 360kb/s.
I think the limit is around 60x, although I have seen many older cd's or cd's that are well used fly apart in a 56x. I suppose you could probably go a bit faster than 60x, but you'd need specialized media.
Amazingly, this new breed of CDRW Drives can burn a complete 700MB CD in about 2.5 minutes!"
My trusty 16x CDRW can burn a 700 MB CDR in about 5 minutes, and faster burners give slightly better performance. (For the uninitiated, faster burners (24x and higher) write most of the CDR slower than their "maximum" speed.) This CDRW is probably only running at 52x for a minor portion of the burn.
OTOH, the CDRW speeds are starting to ramp up nicely. I like using CDRWs to back up files, but even at 10x it can take a while to burn a full disk. For many CDRW enthusiasts, the big story isn't the "quantum leap" from 48x to 52x, its the CDRW speeds.
> It's tough to burn CD's at a decent speed unless you have a 1Ghz+ (Intel speeds) CPU
Uh? I guess that's true if you are running an OS with horrible latencies, but I have yet to make a coaster under Linux (yes it has/had latency issues, but not as bad as other OSs).
A long time ago, when burning at 2x was not-horrible, I started burning a disk and then started Quake 2 on my old P166 with a 3dfx voodoo card and too little RAM, I ran around a few levels while the sound went choppy and the framerate sucked, but the buffer fill on the burner never went below 89%.
Think about it, burning at 2x means having the CPU move 352800 bytes pr. second, any CPU ought to handle that, burning at 50x means moving 8613 KB/s, not exactly high-throughput in todays world, so it all comes down to one thing: "Scheduling Latency", it doesn't matter much how fast your CPU is if your OS is crappy about the latency.
-- To dream a dream is grand, but to live it is divine. -- Leto ][
Actually they are using CLV, but it is Z-CLV (Zone-CLV) burning usually starts around 16x, then ramps up to 20x a little ways into the disc, then to 24x, and so on. If you're only burning a half full disc, you'll never hit the zone where u get into the higher speeds. I wish they would stop with this Z-CLV crap and just do plain old CLV. If they used 52X CLV, then a disc would be able to be burned in about a minute and a half. Z-CLV requires the burner to actually stop burning, spin the disc up to the next zone speed, and then resume the burn. This stopping and starting can introduce errors in the disc, however they are usually taken care of by the ECC built into the ISO9660 format, The error correction on Audio CDs isn't as sophisticated, so u can sometimes hear pops on the disc where the burner stopped and restarted. Also since the error connection is being used to fix errors purposely put there by the burner, it leaves less correction to fix what it was put there for, the scratches that are usually inevitable throughout the life of the disc. If you want to burn discs without this Z-CLV crap, then burn at 16x or lower, 16x or lower on most Z-CLV burners is usually CLV mode. So 1x-16x=CLV, >16x =Z-CLV
Looks like we're getting within an order of magnitude of the theoretical limits of CD-burning! PIO mode 4 caps at 16.7M/sec, which is about 111x, less than double! I bet soon we'll be seeing UDMA or even ATA/66/100/133 CD-R/DVD-R drives... I imagine there's a need for some extra headroom as far as IDE bus bandwidth is concerned...
This actually raises an interesting thought...supposing your drive is 52x at PIO4, would you get a buffer underrun if both the source and destination drive in a burn operation are on the same IDE channel? It would seem, then, that you'd want, at a minimum, slightly more than double the bandwidth of the writer in the IDE bus that it sits on...
Hmmm...
"If at first you don't succeed, lower your standards."
If you already have a 48x drive, then no you shouldn't be impressed. But if you have a 12x, then yes you have my permission to wet your pants and dance around the living room.
There is nothing embarassing about incremental increases in technology. However dancing around the living room in wet pants IS embarassing, even at a New Years Party.
Geez, I thought I'd never find this. It shows the testing procedure for CD-R/RW media by Sony (which put together the Orange Book standards with Philips (and Kodak?)). That should give a little insight as to what's being tested and what would have to be modified to work at a faster speed. I've also wondered about this. Hope it helps.
In the 60's and 70's there were manual card-punches you could use to modify punched cards one column at a time. Slow, but it sure beat waiting in the line at the library for your turn at one of the two IBM keypunches available when your FORTRAN programming assignment is due the next morning.
I would say that would be a better method than the #2 pencil, and more relevant to this discussion of computer-oriented storage.
I have a friend who worked at a place where they used a Frieden Flexowriter to do their word processing. It stored documents on punched paper tape. There was one secretary who was skilled in the craft of splicing the punched paper tape. It was her job to edit and update form letters stored on paper tape.
If you are primarily concerned with audio cd quality then check out Yamaha. Tom's hardware did some analysis on their unique (afaik) audio mastering features a while back.
I hereby inform you that I have NOT been required to provide any decryption keys.
>Thus a burner that creates a cd in 2.5 minutes is 28x
Lead in and lead out times add at least a minute to the overall burn process. At 28x, it'll take 3.5 to 4 minutes to burn the CD. By your logic one could say that it only takes 1.15 minutes to fully burn a CD at 52x. Once you factor in the lead in and lead out times you get closer to the 2.5 minute time previously mentioned.
Not only have Lite-On had a 52X drive out for a while, you can also flash the firmware from an "old" 48X drive up to 52X speed. An "overclocked" Lite-On drive is no different, hardware-wise, than the real thing.
That said, my 48X Lite-On is fast enough for me - and no, I've not burned any coasters writing at that speed. Those of you who believe it's impossible are living in the stone age - high speed writing is here and it works great. And it's cheap! Paid $53 for my drive, and 48X media is no more expensive than slower media - just as with the hardware, as the media improves it replaces the older, slower media at the same price.
There are physical characteristics of CD's that worry me about 52X writing (or reading), however, and that's why I won't go that high - it's not a question of getting a bad write, but a serious issue of exploding discs at such a high rotational speed.
Let's say you're burning an 80 minute CD. At the theoretical max speed of the burner, here's how it breaks down:
speed time improvement
1 80.00 --
2 40.00 50%
4 20.00 50%
8 10.00 50%
12 6.67 33%
16 5.00 25%
24 3.33 33%
32 2.50 25%
40 2.00 20%
48 1.67 17%
52 1.54 8%
Notice that you get a 33% increase going from 8x to 12x, but only 8% going from 48x to 52x. Because speed and time are inversely related, you get a hyperbolic function that gives you diminishing returns on your time savings with each speed increment. You save 40 minutes going from 1x to 2x, but 1:40 going from 24x to 48x. Drives are marketed by speed, but the real benefit to the user is time.
It burns faster toward the outside of the CD. Near the hub, the most you'll get will be 16x or so.
20 January 2017: the End of an Error.