Error Correction Tests

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

- ABEX TCD-721R

Errors total	Num: 872559
Errors (Loudness) dB(A)	Num: 47573	Avg: -73.9 dB(A)	Max: -36.0 dB(A)
Error Muting Samples	Num: 2776	Avg: 1.0 Samples	Max: 11 Samples
Skips Samples	Num: 0	Avg: 0.0 Samples	Max: 0 Samples
Total Test Result	77.0 points (out of 100.0 maximum)

The performance with this disc was very good. Although the total error count was high, the maximum loudness error level at -36.0dB is very good. No samples were skipped. The final score of 77.0 is good.

- ABEX TCD-726

Errors total	Num: 11517940
Errors (Loudness) dB(A)	Num: 101873	Avg: -36.1 dB(A)	Max: -1.9 dB(A)
Error Muting Samples	Num: 117391	Avg: 28.7 Samples	Max: 2705 Samples
Skips Samples	Num: 2905	Avg: 118.6 Samples	Max: 2898 Samples
Total Test Result	44.4 points (out of 100.0 maximum)

The Abex TCD-726 test disc is much easier for drives in general to read. However the Mitsumi drive reported poor performance. The total error count was extremely high, while there were several skips and mutes. That's why we post for both test discs the CDSpeed reading graph. As we can see below, in the CDSpeed graph, DW-7872TE find it difficult to read the contents of the 726 disc.

- 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
Mitsumi DW-7872TE	5/5	5/5	5/5	5/5	0/5

The drive successfully passed the four first out of the five check levels for this test. This is a good performance since the fifth level, which includes artificial scratches of 1.5mm, is difficult for most drives to be read.

- Summary

Test Disc	Reading Speed	Score
ABEX TCD-721R	Max	77.0
ABEX TCD-726		44.4
Average Score		60.7

The Mitsumi DW-7872TE managed an average score of 60.7 out of 100. This is a very low score and it is a resultant of the low 44.4 score of the 726 test disc.