This series of tests checks the drive's ability to correct/conceal possible erroneous data after reading artificially scratched / defective audio discs. The test discs used were the ABEX series from ALMEDIO.

Specifically, a software compares two audio files using FFT analysis. The first audio file has been extracted by a normal audio disc. The second one is the result of the extraction of the another disc which hold the same audio track, but it also has specific defects on its surface. The similarity factor of the the two tracks unveils the error correction capabilities of the drive.

The differences between the two compared tracks are translated to a signal (noise) illustrated in the following graphs. We should note here that this signal is normally appearing here, since there is not any drive capable of fully correcting the serious errors reported for these test discs.

- ABEX TCD-721R

Errors total	Num : 1003189
Errors (Loudness)	55721	Avg:-74.4 dB(A)	Max :-20.1 dB(A)
Error Muting	Num : 3212	Avg : 1.0 Samples	Max : 8 Samples
Skips	Num : 0	Avg : 0.0 Samples	Max : 0 Samples
Total Test Result	76.7 points (of 100.0 maximum)

An adequate score for the LG drive here. There were no skipped samples and the error correction did not start earlier than it should and the Error Loudness sometimes surpassed the -60 dB(A) border. Noise above that value can sometimes become audible, depending on the music that surrounds it.

- ABEX TCD-726

Errors total	Num : 0
Errors (Loudness)	Num : 0	Avg : -174.0 dB(A)	Max : -174.0 dB(A)
Error Muting	Num : 0	Avg : 0.0 Samples	Max : 0 Samples
Skips	Num : 0	Avg : 0.0 Samples	Max : 0 Samples
Total Test Result	100.0 points (of 100.0 maximum)

Pretty good performance here for the error correction mechanisms.

- CD-Check Audio Test Disc

The CD-Check Test Disc is another 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 through a software multimedia player (e.g. 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
LG GH22NS30	5/5	5/5	5/5	0/5	0/5

Playback of the majority of the last two tracks (4 and 5) produced audible noise and interruptions. This is a common score among DVD-RW drives and shows acceptable error correction mechanisms.