About ZCLV?

Do you know any thing about ZCLV? When ZCLV is used?
I appreciate any advises.

Z-CLV stands for Zone Constant Linear Velocity.

It is basically a method for writing disks, mainly at higher speeds.

It is used a lot in DVD Writers as there preferred method of writing at speeds of 8X and above.

What it does is it will say begin at a constant 4X until example the 1GB mark, then it jumps to 6X until example the 2GB mark, finally it will jump to 8X and stay there until the burn process is complete.

this is just an example to give you the idea. Not all jump at the same time, and some have more zones than others. Also the example above illustrated for an 8X burn, obviously it will differ for 12X or 16X. Also drives use it for CD Writing, usually DVD Writers used for CD writing at higher speeds. And also for CDRW disks a lot, even at speeds a bit slower.

Obviously also, some drives do not use Z-CLV at all, and will only us CAV and P-CAV.

Hope this explains.


ZCLV appears to be an easier method of of acheiving accurate laser calibration than CAV or PCAV. This is due to the constant linear speed which means constant calibration. CAV/PCAV requires constant laser adjustment to acheive the best dye temps.

Thanks guys.
My drive is Toshiba SD-R6372 and it has specs that supports burning at 4x with ZCLV and 2x with CLV but actually I can only burn DVD-R at 2x and DVD+R at 2.5x with CLV. May I have media supported ZCLV to burn at 4x or any way to use ZCLV with my drive to burn 4x?
I’m new to DVD burning. Thanks for any advises.

Use 4x or 8x media for 4x writing.

On a 4x DVD writer, 4x is a ZCLV speed (usually!) - on an 8x or above writer, 4x will be a CLV speed.

To get anything other than basic speed/strategy, you must be using media with a code recognised by the writer (updating firmware may help) - the way some media rebranders use various codes with little distinction doesn’t help, and especially in +R media, there is the version number as well.

4x media is more likely to be supported at 4x by older drives, unless the maker is really serious about adding recognition for 8x media at 4x.

So Zone-CLV is the more conservative strategy, and P-CAV is the faster one.
There seems to be a transition in progress in DVD writers, while CD-R seems to be almost exclusivly P-CAV now - a few of the Zone-CLV DVD writers also do CD-R that way.

In CD-RW (Ultra, 24x), Zone-CLV still has a very strong presence, maybe to do with the particular calibration requirements. There are some P-CAV drives, but they are very much the exception.
The other issue, perhaps CD-RW is fading in importance, as DVD rewritable has it outcapacitied and outspeeded. It’s still useful for testing, of course.