DVD Error Correction Tests

Memorex Dual-X1

In the following tests we examined the DVD error correction capabilities of the Memorex DualX-1 drive. For the tests we used CDVD Benchmark v1.21 and Nero CDSpeed . The reference test media comes from ALMEDIO.

- Single Layer media

ABEX TDR-821

This is a single sided, single layer DVD-ROM with a 4.7GB capacity, in which there are scratches with dimensions from 0.4 to 3.0 mm. The following transfer rate picture comes from CDVD Benchmark v1.21. The reference test media comes from ALMEDIO.

The Memorex drive finished the reading test without any problems. During the reading of the scratched area there were no reported errors but right after that the speed decreased from 10X to 6X for an unaccountable reason. Anywise the procedure finished quite well and the performance was good.

ABEX TDR-825

This is also a single sided, single layer DVD-ROM with a 4.7GB capacity. The data structure of the disc is exactly the same as the TDR-821, with the difference that there not scratches on it but defected areas with dimensions from 0.5 to 1.1 mm. There also fingerprints sized from 65 to 75 micro meters.

The drive didn't face any problems to read the disc contents.The Memorex has to reduce from 10X to 5X the reading speed in order to read a specific defected area (fingerprint), but right after the speed increased once again to finish the test with success.

- Dual Layer media

ABEX TDR-841

This is a 8.5GB dual layer, single sided DVD-ROM disc with artificial scratches with dimensions from 0.4 to 3.0mm, in both layers.

Memorex Dual-X1 read the Abex 841 test disc fast without slowing down. No read errors were reported. The drive just ignored the defected areas.

ABEX TDR-845

The disc is a single sided, dual layer DVD-ROM disc with a capacity of 8.5GB. The only difference between the TDR-845 and the TDR-841 is that the first includes defected areas and fingerprints. The dimensions of the defected areas are ranged from 0.5 to 1.1 mm and the fingerprints are sized from 65 to 75 micro meters.

As in the corresponding test with the ABEX TDR-825 (defected single layer DVD-ROM), the drive had no problems to finish the task successfully. The reading speed was again set to 10X at the end of each layer.

ABEX TDV-541

The TDV-541 is a single sided, dual layer DVD-VIDEO disc, with capacity of 8.5GB. The disc is based upon the TDV-540 series which is designed for inspection and adjustment of DVD-VIDEO players. The discs check the layer switch operation from layer 0 to layer 1 and also include test pictures and test signals for DVD sound files. The current TDV-541 checks also the error correction capabilities of the drive and includes scratches from 0.4 to 3.0 mm.

After the end of the 541 test disc NeroCDSpeed reports that the average reading speed is at 5.57X. The drive slowed down at the beginning of the second layer from 8X to 6X and finished the task with speed at 2.76X. The test finished without any read errors.

ABEX TDV-545

The TDV-545 disc is based on the TDV-540 series. It is a single sided, dual layer DVD-VIDEO disc with a capacity of 8.5GB. The TDV-545 includes artificial black dots on the data surface, sized from 0.4 to 1.0 mm. It has also 65 - 75 micro meters fingerprints.

Memorex managed to pass the black dots and the fingerprints very easily. The test was successful, with an 6.18X average speed.