In the following tests we examined the DVD reading capabilities of the NEC ND-3530A drive with scratched / defective DVD media. For the tests, we used CDVD Benchmark 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, and its surface has an artificial scratch of dimensions varying from 0.4 to 3.0 mm.

The following transfer rate picture comes from the CDVD Benchmark v1.21 transfer rate test.

Some minor speed deviations over the last portion of defective area as well as at the end of the disc, but this test disc was not a problem for the NEC ND-3530A, which managed to read the disc, without producing any errors.

ABEX TDR-825

This is also a single sided, single layer DVD-ROM of 4.7GB capacity. The data structure of the disc is exactly the same as that of the TDR-821, with the difference that there are no scratches on it but instead, defective areas of dimensions ranging from 0.5 to 1.1 mm.

There are also fingerprints sized between 65 and 75 micrometers.

Again, the drive read the disc without problems. With both single layered test discs, the ND-3530A reached its maximum 16x reading speed. Very good error correction capabilities with single layered DVD media.

- Dual Layer media

ABEX TDR-841

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

In this case, the drive needed to lower its speed over the defective areas to read the disc. The second layer was particularly troublesome, but on the other hand, no read errors were produced.

ABEX TDR-845

The disc is a single sided, dual layer DVD-ROM disc of a capacity of 8.5GB. The only difference between the TDR-845 and the TDR-841 is that the first includes defective areas and fingerprints.

The dimensions of the defective areas range from 0.5 to 1.1 mm and the fingerprints are sized from 65 to 75 micro meters.

Very good correction with this disc where drive easily bypassed the defective areas and fingerprints without the need to lower its speed. Very good performance from the NEC drive.

ABEX TDV-541

The TDV-541 is a single sided, dual layer DVD-VIDEO disc, with a capacity of 8.5GB. The disc is based on the TDV-540 series which is designed for inspection and adjustment of DVD-VIDEO players. The disc checks the layer switch operation from layer 0 to layer 1 and also includes test pictures and test signals for DVD sound files.

The current TDV-541 also checks the error correcting capabilities of the drive and includes scratches from 0.4 to 3.0 mm.

The scratched area was read without any errors. This indicate excellent DVD error correction capabilities.

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 meter fingerprints.

Again, the ND-3530A proved to be a very good reader when it comes to problematic media. Black dots and fingerprints were not a problem.

- Summary

As you can see from all the graphs above, the ND-3530A managed to pass all these demanding tests without problems. However, it is not the fastest reader around but it sure does the job. After all, with these tests, we aim to see DVD error correction capabilities, and not reading speed performance. As many of you may think,: better late than never from NEC.