Error Correction Tests

In the following tests we check the drive's behaviour when reading scratched / defective audio discs. The test discs used were the ABEX series from ALMEDIO.

- ABEX TCD-721R

The drive performed very well with the ABEX TCD-721R test disc, returning a very low count on the number of loudness errors with an average of -73.6 dB. Muting error count was also negligible and there were no samples skipped. The total score of 76.8 is quite good as is the C2 accuracy score of 99.7.

- ABEX TCD-726

The Abex TCD-726 test disc is much easier for drives in general to read, and as such, the Pacific Digital U-30201 drive corrected almost all errors with a perfect quality score of 100 points. Any loudness errors recorded were too low ( average of -174.0 dB) to register on the graph.

- CD-Check Audio Test Disc

The CD-Check Test Disc is a very useful tool for evaluating the Sound Reproduction / Error correction capabilities of a CD player. The disc offers a signal combination with disc error patterns to rate the drive's abilities to read music and reproduce it completely. Five tracks on the disc contain a sequence of progressively more difficult tests. These tracks are referred to as Check Level-1 through Check Level-5.

The tracks are reproduced (played) through a software multimedia player (i.e. Windows Media Player). Each level is considered as passed, if the tone coming out from the speakers is smooth, continuous without interruptions, skipping or looping. The higher the Check Level passed, the more reliable the sound reproduction of the tested drive.

The drive succesfully passed the first 3 check levels for this test. Playing the 4th and 5th tracks produced a constant noise in the background. It appears that the drive is capable of "correcting" errors created by scratches with size less than the 1.125 mm present on the 4th check level although it was a little surprising that it couldn't pass the 4th check level considering the good results returned in the tests with the ABEX TCD discs previously. The 5th check level, which has a scratch a size of 1.500 mm, is difficult to read with most drives.

- Summary

Combining the two scores from the ABEX tests gives an average total score of 88.4 points out of 100. This is a very good overall score. Not surprisingly, it is the exact same score achieved by the LiteOn LDW 811S, and in fact, the graphs and figures are nearly identical for the two drives.