 # Plextor Premium 10-24X CAV

#1

Does anybody know what 10-24X CAV means for the Q-Check C1/C2 Test?

Apparently the reading speed should start at 10x, and then grow linearly, reaching 24x at some MSF, say M. What is the value of M?

The time T (in min) to read a disc of effective size S (in min) should be about

T = (M/14) * ln( 1.4 * S / M + 1 )

where ln denotes the natural logarithm. For instance,

M = 70 min, S = 70 min => T = 4:23 min,
M = 70 min, S = 80 min => T = 4:47 min,
M = 80 min, S = 70 min => T = 4:34 min,
M = 80 min, S = 80 min => T = 5:00 min.

We could estimate M if Plextor Premium owners reported the values of T observed for given values of S. (Unfortunately I don’t own this drive.)

For a given disc, one gets S as the MSF displayed by Q-Check and T by measuring the elapsed time (preferably with the spin-up time excluded). It would be good to include the C2 count as well. Namely, we could estimate M from discs without C2 errors, and use the remaining data to check if the reading speed decreases when problems occur (as in CD Speed).