The specifications of the NEC ND-7551A state that the drive is able to write CD-R discs at 24x and CD-RW at 20x. Let us find out how the drive really performs in speed and quality.

Writing Data CD-R discs:

For our data writing tests, we simply set up a new compilation of 700Mb using Nero Burning ROM software. Writing method used is DAO (Disc At Once), and the disc is set up as a non-multisession disc with “finalize disc” enabled. The screenshot below shows how long it takes to write a disc at the highest speed. (24x):

The drive used 6 minutes and 18 seconds to write the disc at 24x.

Write Quality:

We will test CD-R discs from different CD-R manufacturers. To really measure the write speed, we used the “create data CD” function in Nero CD-Speed. The discs were written at the maximum speed that the drive supports. For the quality test, we used KProbe 2 which is a tool developed by a Lite-On employee. It runs under Windows and works with drives made by Lite-On. Also note that different drives and different reading speeds may affect the results obtained when scanning the discs. We used a Lite-On LTR-48125W drive with firmware VS0D and scanned the discs at 48X speed.

A written CD-R disc will always have some C1 errors; C1 errors are easily corrected by the drive’s error correction capabilities. The next level of errors is C2, while C2 errors could also be corrected by most drive’s error correction capabilities; they are not wanted on a good quality disc. A good disc should not contain any C2 errors, and preferably have an average C1 error amount of below 2.0 for the best discs, or at least below 10.0 averages for good quality discs. After C2 errors, there are only un-correctable errors that will make a disc unusable.

Below are the obtained results:

We have already seen better results, but reading this disc should not cause any problems. 

MMORE media – manufactured by Moser Baer India Limited with an average C1 of 11.29 gives an OK result.

NewStar Digital media made by Infodisc had some C2 errors. Since there are some coloured spots visible on the disc, the drive probably cannot be blamed for this result. The disc was only written at 16x.

Traxdata media made by RiTEK gave a good result on the ND-7551A although there is a slight increase of C1 errors in the middle of the disc.

Media made by Taiyo Yuden have always had a good reputation and with the average C1 errors of 3.87 it goes into the “good quality discs” category.

Verbatim – a well-known brand showed us a C1 average of 0.94 – highly recommended disc for this drive.

Writing Quality with Re-Writable discs:

Due to requests from our readers, we will add a few write quality tests with re-writable media. Settings and testing procedures is the same as used earlier in this review, so you may want to go back and read them if you are unsure.

CD-ReWritable media:

24x CD-RW media made by Infodisc, we notice increasing C1 errors in the middle and at the end of the disc and due to the C2 errors at the end of the disc we cannot recommend this media.

Memorex 12x CD-RW media made by Infodis, the result of this disk is good with the C1 average of 5.88

12x CD-RW media made by RiTEK, the KProbe scan shows high C1 and C2 spikes which makes it impossible to recommend this media.

Although the C1 errors are very high at the end of the disc, it should still be readable.

Summary:

The CD-R writing quality is OK, but the CD-RW quality still needs to be improved.

So let us head on to next page and read about DVD-Writing performance…

Reading performance

DVD+R/RW Writing performance