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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!"
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.
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."
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.
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.