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

- ABEX TCD-721R

Errors total	Num: 3205447
Errors (Loudness) dB(A)	Num: 149658	Avg: -75.2 dB(A)	Max: -18.1 dB(A)
Error Muting Samples	Num: 9769	Avg: 1.0 Samples	Max: 5 Samples
Skips Samples	Num: 20	Avg: 6.0 Samples	Max: 6 Samples
Total Test Result	65.0 points (out of 100.0 maximum)
C2 Accuracy	99.6 % (out of 100.0% maximum)

Ricoh performed poorly with the ABEX TCD-721R. The drive's average error loudness was at -75.2 dB(A) and the total score of 65 points isn`t good. The total error count of 3205447 is very high and there were 20 skipped samples. We must also note that C2 accuracy reached 99.6%, an almost perfect score.

- ABEX TCD-726

Errors total	Num: 4278
Errors (Loudness) dB(A)	Num: 7856	Avg: -83.1dB(A)	Max: -56.5 dB(A)
Error Muting Samples	Num: 72	Avg: 1.0Samples	Max: 1 Samples
Skips Samples	Num: 0	Avg: 0.0Samples	Max: 0 Samples
Total Test Result	82.3 points (out of 100.0 maximum)
C2 Accuracy	100 % (out of 100.0% maximum)

Ricoh had better performance with ABEX 726 disc with total score of 82.3 %.

- 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.

Error Level	1	2	3	4	5
Plextor PX-708A	5/5	5/5	0/5	0/5	0/5

The drive passed only the first two Check Levels of the test. The performance reveals lower than average sound reproduction and error correction. The fifth level includes an error size of 1.500mm, where the drive produced many audible clicks.

- Conclusion

The overall performance of the Ricoh MP5308D was rather poor, since when the drive encounters even small scratches produces large spikes and can't correct them. NEC should really improve the drive's performance, by fine tuning the firmware.