Between two fires?

Hi - I have two ‘identical’ bulk Philips 1640s, cross-flashed by an identical process to BenQ EW1621 47L9 firmware; they’re in identical PL-3507-chipset external enclosures, also with identical firmware, & are connected through the same Firewire host to the same workstation.

One of these is for a friend, so I thought I’d run a few tests to make sure he got the better one. One of these test-series involved using CD-DVDSpeed 3.61 to repeatedly quality-test the same DVD - a ‘Datasafe’ brand MMC003 burned at 12x.

i’d be interested to see who in this forum comes to the same decision as I have: first, a compound snap of the figures from five runs in the first EW1621:

Second, a compound snap of the figures from another five runs in the second EW1621 - (BTW - all runs in both burners produced the same ‘quality rating’ of 97%)

Next; a compound of the PIFs from the same five runs in the first EW1621:

. . then the same thing for the second EW1621:

I’m interested in seeing the PI Errors. It seems that the only difference is how they are being read between 4GB and the end.

The error pattern at the end of the disc on the first drive is in the low-solid-block pattern indicating a mild communication interference. Scanning at higher speeds is necessary to determine if greater errors are actually present on the disc.

Ah, scan the all of the output/test discs (from both drives) in just one drive (the second drive).
We can’t compare written output that is SO close without a common point of reference (write discs with both, but scan with just one drive).

Also, try the latest cd/dvd speed from and manually set the scan speed to 12x as this [is the burn speed used and] will magnify the differences.

Next repeat the test using the first drive to scan all of the output/test discs. Use the same cable–do not switch cables or ports–switch only the drives.