detail information

Writing Data CD-R discs:

Let us first take a look at the CD-R write technology used by the Lite-On SHW-1635S:

As we could see, the Lite-On SHW-1635S uses CAV (Constant Angular Velocity) to write at its rated speed of 48x, this gives an average speed of 37.18x. Look below for comparison with two other drives.

The BenQ DW1640 uses CAV (Constant Angular Velocity) to write at its rated speed of 48x. This gives an average speed of 35.20x.

As we could see the Samsung SH-W162C uses CAV (Constant Angular Velocity) writing strategy to reach it rated speed of 48X. This gives an average speed of 37.01x.

And as a last test, we wrote a disc containing 700Mb using Nero Burning ROM software. Writing method used is DAO (Disc At Once), and the disc is set up as a non multi-session disc with 'finalize disc" enabled.

Nero 7 is pretty stupid and closes the overview window automatically, so this is the only image we have to show from the writing process. By manually calculating the time used we could see that it used 2 minutes and 39 seconds for writing the disc.

Excellent! Nothing more, nothing less, it simply outperforms all the other drives, but is the writing quality good? Let's find out!

Write Quality:

We will test CD-R discs from a total of 9 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-52246S drive with firmware 6S0F 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 C1 average below 10.0 for good quality discs. After C2 errors there are only un-correctable errors that will make a disc unusable.

Why wait any longer? Below are the obtained results:

The CMC Magnetics discs seem to be pretty good; they work very well with Lite-On SHW-1635S at least.

While the error level is good the writing speed of 16x is not, Lite-On should really look into adding support for this media at higher speeds.

Excellent quality with Mitsubishi/Verbatim media, highly recommended.

No problems with Ritek media either, but notice that the quality of Ritek CD-R media may vary greatly.

First 56x certified media we've ever seen, but Lite-On SHW-1635S supports it at 40x only. The quality result is good though.

And Taiyo Yuden gives excellent results as it should.

The result is good with this media too, but it's only supported at 40x writing speed.

Not the highest quality media, but the result is still very good.

No problems with this media either.

CD-ReWritable:

The Lite-On SHW-1635S supports a CD-ReWriting speed of 24x; let us see how this compares to other writers. Let us start with taking a look at the writing strategy it uses:

The Lite-On SHW-1635S uses Z-CLV, (Zone-Constant Linear Velocity), to write at its rated speed of 24x, this gives an average speed of 22.57x. Let us see how this compares to two competing drives.

The BenQ DW1640 uses P-CAV (Partial-Constant Angular Velocity), to write at its rated speed of 32x, this gives an average speed of 30.33x.

The NEC ND-3540A uses Z-CLV, (Zone-Constant Linear Velocity), to write at its rated speed of 32x, this gives an average speed of 29.75x. 

Below, a comparison table with results from other writers.

It's slower than most other drives due to most other drives supporting 32x writing speed, we would like to see 32x CD-ReWriting speed from Lite-On as well. But maybe the lower writing speed will give better quality results? Read on to find out.

We have seen worse, but there is still room for improvements.

Luckily there are no C2 errors, but the C1 error level is still pretty high.

The result with this media is not good as there are several C2 errors near the end and the C1 error level is very high too.

Summary:
The Lite-On SHW-1635S is currently the fastest DVD-Writer we have tested when it comes to writing CD-R media. And the writing quality is very good too! The media compatibility could be improved though. For CD-RW it fails to impress as it only supports 24x writing speed and the writing quality is not very good either.

But after all, it's a DVD-Writer, so head on to next page and read about DVD-Writing performance and DVD media compatibility…