CD 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

Errors total	Num: 985862
Errors (Loudness) dB(A)	Num: 51899	Avg: -60.5 dB(A)	Max: -11.3 dB(A)
Error Muting Samples	Num: 3012	Avg: 1.8 Samples	Max: 1140 Samples
Skips Samples	Num: 0	Avg: 0 Samples	Max: 0 Samples
Total Test Result	76.5 points (out of 100.0 maximum)

The Philips drive did not present any particular problems during this test, producing acceptable results, although the maximum loudness error level is such that it makes us believe that it could lead to audible clicks. The total score of 76.5 however, is quite good.

- ABEX TCD-726

Errors total	Num: 0
Errors (Loudness) dB(A)	Num:4	Avg: -94.0 dB(A)	Max: -87.6 dB(A)
Error Muting Samples	Num: 0	Avg: 0.0 Samples	Max: 0 Samples
Skips Samples	Num: 1	Avg: 185 Samples	Max: 185 Samples
Total Test Result	83.6 points (out of 100.0 maximum)

The Abex TCD-726 test disc is much easier for drives in general to read, and here the Philips drive performed better in comparison to the previous test disc. One sample was skipped. The score of 83.6 is good although we have come to expect better.

- 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.

Error Level	1	2	3	4	5
Philips JR4DVDRW	5/5	5/5	5/5	5/5	0/5

The Philips JR4DVDRW managed to playback successfully the first four tracks, which reveals that the drive has good error correction capability with audio discs. Although the the 5th check level was not read by the drive, we should mention that it contains a scratch with a size of 1.500 mm and is difficult to read for most drives.

- Summary

Test Disc	Reading Speed	Score
ABEX TCD-721R	Max	76.5
ABEX TCD-726		83.6
Average Score		80

Combining the two scores from both of the ABEX tests, the Philips drive gives an average total score of 80 points out of 100. This is a good score, but it places the drive somewhere in the middle of the rankings.