To round off this review, we will run some advanced tests on the NEC ND-7551A. These tests are the “Sheep Test” and some special disc tests.

The “Sheep Test”:

 For this test, we will use the Sheep tests made by Alexander Noé. Why is it called sheep test? That’s because the logo of the first 1 to 1 copy program called CloneCD is a sheep. When looking at supported writers, you will notice that the feature list has sheep to indicate if a feature is supported or not. In this case we are interested in the writer’s ability to backup/write weak sectors. Also called: “Correct EFM encoding of regular bit-patterns”.

No sheep: Can’t backup any Safedisc 2 versions without the help of software tricks

1 Sheep: Can backup Safedisc 2 up to version 2.4x without software tricks

2 Sheep: Can backup Safedisc 2, including version 2.5x

3 Sheep: Can write all possible weak sectors, few if any writers could do this.

One of our forum moderators Womble, has written a guide concerning the “Sheep Test” that can be found here.

In the screenshot below taken from CloneCD, we see the NEC ND-7551A supports everything.

The NEC ND-7551A supports DAO-RAW recording mode, which basically means, it can write uncorrected data and sub-channel data.

As we can see from the table the NEC ND-7551A is a “Two Sheep Burner”, but it however failed to write the Safedisc V2.90 and Sheep3 tests.

Overburning:

To test the overburning capabilities of the NEC ND-7551A, we used the over-burning test in Nero CD/DVD-Speed.

CD-R:

For this test we used an Infiniti Professional Compax 99min/900mb CD-R.

According to Nero CD/DVD speed the drive can overburn around 93 minutes. Higher values than the one above resulted in an error message.

To test if the NEC ND-7551A is capable to read overburned CD-Rs, we used a 90:51:25 minutes CD-R:

As we can see for the picture above the NEC ND-7551A had no problems reading the 90:51:25 minutes CD-R.

 DVD+R/-R:

We also tried to overburn DVD+R/-R media:

According to Nero CD-DVD Speed this function is not supported on DVD+R/-R media by the NEC ND-7551A.

Mini DVD-R/RW discs:

In this section we are going to test if the NEC ND-7551A is capable to write and read mini DVD-R/RW discs with a capacity of 30 minutes/1.46 GB.

The NEC ND-7551A had no problems to write or read the Traxdata Mini DVD-R disc made by RiTek Corporation, the PI however could be a bit lower in the area that was written at 2x. Let us try a Mini DVD-RW disc:

Again, the NEC ND-7551A had no problems to write or read the Traxdata Mini DVD-RW disc and even the KProbe scan shows an excellent result.

Labelflash

Conclusion