A 4x BD-R disk burned at 6x - is this ok?



I bought a TDK BD-R 4x 50GB disk (CMCMAG-DI6-000) and told ImgBurn to burn it at max speed. ImgBurn, apparently, tested all speeds and concluded that it can be burned at 6x.

The disk burned successfully and it was verified by ImgBurn itself.

However 6x is more than the 4x promised in the box.

My question is: is this safe for the longevity of the data on the disk?


Hard for anyone to say with any kind of certainty unless they have the same drive as you and have done some tests with these particular dics. Some media can be burned faster than the rated speed with no issues. Others don’t do as well. With this CMC made DL Blu-ray, I think I would stick to 4x from here on out.

Which burner do you have?



So it’s perfectly ok to burn a 4x medium in 4x or is it going to be a more quality burn at 2x or 3x?


Again, I can only speak in general terms. Slower isn’t always better. Depends on the firmware of the drive you are using, and how well it matches the media.

Many of our members do testing of various types of media. This thread shows CMC DL discs being burned with different drives at different speeds: http://club.myce.com/f179/cmc-magnetics-bd-r-dl-320822/

I’d probably try burning at 4x for now, and if you have a Lite-on burner, you can do some quality tests with Opti Drive Control.


Typically, if the disc is a high quality one, it can be burned faster. My Pioneer lets me burn 4x Panasonic DL BD-R at 10x and quality scans show it’s more than fine at that speed.

As Kerry said though, it’s hard to say without quality scanning to show potential issues. Verifying the burn is almost useless as you only know it can be read back. It could be almost unreadable but if the drive struggles and gets through, it will pass.

I’d use opti drive control app and do a transfer rate test. That can at least show if the drive struggles to read the disc (large speed dips during read back).


You can just view the graph data file for that. Verification is a 2 in 1 in that sense.


After media TDK BD-R DL code MID: CMCMAG-DI6-000 is to write gear x6.
For recording gear x4 was TDK BD-R DL code MID: TDKBLDRFB whose production ended in March 2013.


^So you have discs which were designed to support 6x writing, but were just labeled as 4x.