|Kenwood 52X TrueX Specs|
||CD-R, CD-RW, CD-Extra|
||Photo CD, Karaoke CD|
||CD-1/Mpeg, CD-WO, I-Trax CD|
|Claimed Sustained Transfer Rate
|Claimed Burst Transfer Rate
|Average Random Seek Time
||40-pin EIDE Header|
||4-pin analog, 2-pin SPDIF digital|
Where's the "Max"?
Just based on ratings along, the 52X is the fastest drive we've received. But what does this "TrueX" mean? As described in detail in our Asus 50x Max CD-ROM review
, the vast majority of high-speed CD-ROMs today use a method of reading discs known as CAV, or Constant Angular Velocity
. This method will spin the disc at a constant rate (for the Asus drive, at 10,000 RPM), and thus the pick-up heads will read the disc at different speeds depending on where the data is located on the physical disc.
There are a few disadvantages to using this method. First of all, data will only be read at the "Max" speed if it's on the outer rim of the disc. Data on CD-ROM is stored from the inside-out, which means that you won't be able to take advantage of the "max" speed unless you're reading data at the end of the disc, a less-than-ideal situation.
Linear - straight as an arrow
This is where it gets a little confusing. "True-speed" CD-ROMs read data at Constant Linear Velocity
, or CLV. These drives will change the speed of the disc depending on where the read-head is operating. Need the center of the disc, where it spins the slowest, the motor will speed up to increase the data read rate. Near the outer edge, where the disc spins faster, the drive will slow down the rotation rate to keep the data transfer steady.
CLV drives stay more true to their claims of "10x or 16x" than CAV drives, but in general they tend to be available only at slower speeds, since it's harder to dynamically vary the rotation rate of the disc in relation to the position of the read head's laser.