dolphinius_rex wrote:Firmware can deffinately affect a drive's ability to scan a disc... but jitter is not the be all and end all of scanning either unfortunately. I've already noticed difference between how a DW1620 and DW1640 scan for jitter (the DW1640 is more forgiving, while the DW1620 is less forgiving).
Sadly, for a really good view of a disc's quality, the best way is still to test it on multiple drives. That way you can analyze several perspectives on the disc, and come to a more rounded conclusion. This is the basis for my own testing.
According to my friends with more than 10 years of expertise in the optical disc industry, jitter measured with CATS is the be all and end all of scanning. As to consumer drives, it is unfortunate that leading jitter and trailing jitter cannot be measured separately at present. Moreover, only those machines based on Philips and Ali chipsets are endowed with the capability to report jitter in non-arbitrary unit. Let’s hope that things will improve in the near future.
The differences between the performances of Benq 1620 and 1640 in your tests are generally not large, and may be considered as variations between drives, for consumer products are not carefully calibrated as CATS is. I shall wait until the graphs in your forthcoming review are online to see if I have some more comments to make. BTW, have you compared jitter levels given by Benq 1620 and by 1640 with those by CATS? If yes, which is closer to CATS in this respect?
I am also of the opinion that it is essential to use at least two consumer drives to conduct tests for reviewing purposes, even if all of them can report jitter, as they are not made with the same components and calibrated exactly. But most people may not want to spend money to buy another drive. I like the combination you have chosen to use, especially Plextor 712, as it gives PIE rates at 8X or 12X speed more or less the same as CATS.