Read Rates, Part 2

The relatively normal behavior of green and blue CD-Rs stands in contrast to some very odd behavior we found with original CDs on this drive.  We ran the CDSpeed99 test repeatedly, and often obtained widely different results.  Most of the time, however, we found the following:

The drive seems to leave a very normal impression over the majority of the CD before breaking off suddenly at the end. We found this behavior when testing every different variety of original CD imaginable.   But that’s not all: we also saw something similar in the very middle of CDs:

In both cases, the drop at the end is very apparent, without which the drive probably would have exceed the 50x mark.  With less than fully written CDs, we generally saw no problems at all, as the following diagram shows: