Submit Hint Search The Forums LinksStatsPollsHeadlinesRSS
14,000 hints and counting!


Click here to return to the 'Rip CDs at Mach 2 on a Mac Pro' hint
The following comments are owned by whoever posted them. This site is not responsible for what they say.
Rip CDs at Mach 2 on a Mac Pro
Authored by: kirkmc on Oct 27, '06 08:36:19AM
From http://arstechnica.com/reviews/1q99/truex52-1.html:

"Newer drives are CAV, or Constant Angular Velocity, drives. With CAV, the rotational speed of the disc is constant. Since the data track has a smaller radius on the inside of the disc, if speed remains constant as the read head moves inward, the amount of data read during a rotation of the disc will be smaller than at the outside of the disc. Thus we get a range of speeds. A typical 40X CAV drive is really a 16X-40X drive--16X at the inside, 40X at the outside. Few manufacturers go to great lengths to point out this fact, publicizing only the highest rate."

---
Read my blog: Kirkville -- http://www.mcelhearn.com
Musings, Opinion and Miscellanea, on Macs, iPods and more

[ Reply to This | # ]

Rip CDs at Mach 2 on a Mac Pro
Authored by: Unsoluble on Oct 27, '06 01:41:48PM

Interesting to see that the newer drives run at a constant speed. Not sure when they changed that, but I've got a Discman here from a few years back that has a little window in it, and you can quite easily see the rotational speed changing drastically from start to finish.



[ Reply to This | # ]
Rip CDs at Mach 2 on a Mac Pro
Authored by: dethbunny on Oct 27, '06 02:25:35PM

It depends on the needs of the drive. If you play an audio CD in a computer, it'll keep playing at a constant data rate, while spinning more slowly at the end. Think of it this way - if the drive can spin at 5000 RPM and read data at 15X (totally made-up numbers there) in the middle, why artificially slow down to keep reading at 15X all the way through? Why not spin at 5000 RPM all the way, and reap the speed gains as the tracks get gradually longer? That's what modern drives do. Since it's generally desirable to read data as fast as possible, they maintain a constant angular velocity that is always as fast as a particular disc can be reliably read.



[ Reply to This | # ]