Error correction is a very important feature of any optical drive. The correct reading of a sector depends on both the optical system of the drive and the hardware correction mechanisms at the drive level. It is often the case that after a few tests we get different results. In this situation, we present an averaged result.

CD DAE

The CD DAE program is used to rip music from audio discs.  Each track is read twice.  During the second run, the program compares both results and any differences are treated as read errors.  The less read errors - the higher the drive rating.

Correction - discs containing data.

Once again we will use Nero CD Speed ​​- Scandisk / Surface.  The result is a graphic representation of any damage to the disc.  Green areas indicate error-free sectors, yellow areas indicate that the drive used its error correction mechanism when reading.  Red indicates bad sectors that the drive cannot read properly.

Read the recorded CD-R too fast.

When disc manufacturers use low quality or higher speed discs, damage may occur to the sectors.  These errors may result in an inability to read the recorded data, and even worse, nothing informs the user about the resulting errors.  Nero CDSpeed ​​and Scandisk / Surface are able to graphically display the damage to a recorded disc (see below).

Reading of heavily scratched single-layer DVD embossed disc, with many scratches on its surface.

Correction - file read test.

 The surface test performed by CD-DVD Speed ​​allows you to graphically illustrate the error correction of the drive.  However, the most useful information is obtained by performing data readings from damaged discs.  We used two CDR, DVD + R and BD-R DL media which were scratched.  We used the CDCheck software to test the amount of recoverable data from the media.

Result of readings for CDR: 100% 
Result of readings for DVD + R: 54% 
Results of data read for BD-R DL: 24%

Access times for CDs \ DVD \ BD are typical for most multi-media designs.

Random CD access (180ms factory data) achieved in media-specific tests was in the ~ 160ms - 180ms range.

Random DVD access (180ms factory data) achieved in media tests was in the ~ 170ms - 190ms range.

Random access to Blu-ray (180ms factory data) achieved in media tests was in the ~ 170ms - 230ms range.

So, we were able to achieve very similar test results as the averaged data in the factory specifications.

Summary:

The drive offers poor data correction when reading CD, DVD and Blu-ray media.  On the other hand, the result from the CD DAE test was correct.  The drive coped well with the fast-burning CD-R.  Based on the CD-DVD Speed ​​Test, you could recover most of the data from the fast-burning CD-R.  On the other hand, heavily scratched or worn CDs, DVDs and BDs present a big problem for the reading/ correction mechanism offered by the drive.  Access times are better than those listed in the technical specifications.