Error Correction Tests

In the following tests we check the drive's behavior when it comes to reading scratched / defected discs. The test discs that we are using are the ABEX Test disc series from ALMEDIO.

- ABEX TCD-721R

Errors total	Num: 1101429
Errors (Loudness) dB(A)	Num: 51457	Avg: -73.2 dB(A)	Max: -21.9 dB(A)
Error Muting Samples	Num: 3443	Avg: 1.0 Samples	Max: 11 Samples
Skips Samples	Num: 0	Avg: 0.0 Samples	Max: 0 Samples
Total Test Result	76.7 points (of 100.0 maximum)

As you can see from the graph, the drive performed quite well. Many errors were corrected, and the the error hiding capabilities of the drive are high, since the average level of the signal is less than -60dB (-73.2dB). According to EAC author, such level is acceptable and does not lead to audible problems in the output signal.

In addition no synchronization errors occurred, resulting to an overall score of 76.7 points our of 100.

- ABEX TCD-726

Errors total	Num: 0
Errors (Loudness) dB(A)	Num: 0	Avg: -174.0 dB(A)	Max: -174.0 dB(A)
Error Muting Samples	Num: 0	Avg: 0 Samples	Max: 0 Samples
Skips Samples	Num: 0	Avg: 0 Samples	Max: 0 Samples
Total Test Result	100.0 points (of 100.0 maximum)

According to EAC, the comparison of the original .wav file with the defected one gave no differences, which means that the drive managed to make an accurate rip of the defected disc. The performance is high and the total test result of the drive is the perfect 100.0.

- Conclusion

Test Disc	Reading Speed	Score
ABEX TCD-721R	Max	76.7
ABEX TCD-726		100.0
Average Score		88.35

LiteOn DVD+RW LDW401S gets very good average score of 88.35 points with the 721R and 726 Abex test discs. The drive corrected a high percentage of the faulty bits and managed to hide many errors. The 726 test disc was read with remarkable accuracy and this means that LiteOn LDW-401S is tuned to perfectly handle errors lower than one critical level. Our though is that this level is high enough to cover your everyday needs.

- 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 difficult tests. These tracks are referred as Check Level-1 through Check Level-5.

The files 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 device.

Each file was played 5 times. A 5/5 score donates that the file was played flawlessly without problems.

Error Level	1	2	3	4	5
LiteOn LDW-401S	5/5	5/5	5/5	0/5	0/5

LiteOn LDW-401S successfully passed the first 3 Check Levels of the test. The performance reveals good sound reproduction and error correction. The fourth level includes an error size of 1.125mm, and the drive gave back audible clicks. The fifth level could also not be played correctly. As we also mentioned in the EAC tests, the drive performs perfectly below the critical "threshold", which is the 1.125mm scratch in our case.