CD Error Correction Tests

In the following tests we check the drive's behavior when it comes to reading scratched / defective discs. The test discs we used are the ABEX series from ALMEDIO.

- ABEX TCD-721R

Errors total	Num: 1288108
Errors (Loudness) dB(A)	Num: 62011	Avg: -72.3 dB(A)	Max: -6.9 dB(A)
Error Muting Samples	Num: 4711	Avg: 1.3 Samples	Max: 605 Samples
Skips Samples	Num: 104	Avg: 19.9 Samples	Max: 588 Samples
Total Test Result	60.7 points (out of 100.0 maximum)

The DRU-540A performed poorly with the ABEX TCD-721R. The total error count of 1288108 is about average, but the level at -6.9 dB(A) is very high and may lead to audible errors. Consequently, the number of skipped samples is also very high. The low total test result score of 60.7 out of 100 is justified.

- ABEX TCD-726

Errors total	Num: 1293530
Errors (Loudness) dB(A)	Num: 61996	Avg: -72.4 dB(A)	Max: -7.6 dB(A)
Error Muting Samples	Num: 4703	Avg: 1.3 Samples	Max: 599 Samples
Skips Samples	Num: 93	Avg: 7.2 Samples	Max: 30 Samples
Total Test Result	63.0 points (out of 100.0 maximum)

The performance with this test disc was quite the same with the previous case, which was not expected since this disc is much easier to read. The total test result of 63.0 out of 100 at best average, since we have seen since there are many drives that achieve scores close to 100. Overall, the performance for this series can be considered below par.

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 being reproduced through a software multimedia player (i.e. Windows Media Player). Each level is considered as passed, if the tone 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
SONY DRU-540A	5/5	5/5	5/5	5/5	0/5

The drive passed the first four Check Levels of the test. The performance is very good offering better than average error correction capabilities. The fifth level, which includes an error size of 1.500mm, produced many audible clicks with the drive.

CD error correction is not one of the Sony drive's strong points. Performance could be better...