Page 4 CD-R/RW discs Writing Performance

The specifications of the LG GGC-H20L state that the drive is able to write CD-R discs at 48X CD-RW discs at 32X. Let’s find out how the drive really performs in speed and quality.

Writing Quality with CD-R discs:   

For our data writing tests, we simply set up a new compilation of about 702Mb 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 (16X):

The drive took 2 minutes and 52 seconds to write the disc at 16X.

Write Quality:   

First we test CD-R discs from different CD-R manufacturers.  To measure the write speed we will use the “Create Data CD” function from within Nero CD-DVD Speed.  We wrote these discs at the maximum speed that the drive supports.  For the quality test, we will be using Nero CD-DVD Speed.  CD-DVD Speed runs under Windows and supports several drives.  Also note that different drives and different reading speeds may affect the results obtained when scanning the discs. For our CD scanning we will be using a Lite-On SOHR-5239V with Nero CD-DVD Speed scanning at 52x speed.

Disc Quality Scanning – C1/C2 (and CU); here is an explanation in more detail:

CDs use an error detection and correction system (CIRC) which is for the most part not seen by the user when reading the disc.  We can get a working idea of the quality of the media in question by performing Disc Quality Scanning that will show us the amount of errors the drive is detecting and correcting while reading the media.

There is more than one way to handle C1 and C2 error detection/correction, but a simple and common way is to detect and correct up to two errors per frame in each stage and detect three or more errors:

• E11: 1 error detected and corrected by C1 layer

• E21: 2 errors detected and corrected by C1 layer

• E31: 3 or more errors detected but not corrected by C1 layer

The sum of these (per second) is called the BLock Error Rate: BLER=E11+E21+E31

• E12: 1 error detected and corrected by C2 layer

• E22: 2 errors detected and corrected by C2 layer

• E32: 3 or more errors detected but not corrected by C2 layer

Any E31 is uncorrectable by the C1 layer and will result in the bytes in that frame being redistributed into multiple frames which are passed to the C2 layer.

Any E32 is uncorrectable by the C2 layer and will result in interpolation being used for Audio CDs or will result in third layer error correction being use for Data CDs.

Different drives have different ways of reporting these errors in a Disc Quality scan.  Lite-On CD-RW drives will report C1 and C2 errors this way:

• C1=BLER=E11+E21+E31

• C2=E32

Here is a little easier way to look at Disc Quality Scanning:

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 quality discs, or at least below 10.0 C1 average for good quality discs. After C2 errors, there are only un-correctable errors that will make a disc unusable.

In short, our analysis will be based on this guideline to determine the quality of the burned disc:

CD-R/RW quality scans guideline

And below are the obtained results:

Taiyo Yuden media has low C1 errors and no C2 errors so it goes in the “Best Quality” category.

Maxell media – manufactured by RiTEK Corporation has low C1 errors and no C2 errors so it goes in the “Best Quality” category.

Memorex Music media – manufactured by CMC Magnetics has no C2 errors and low C1 errors so it goes in the “Best” category.

Verbatim media – manufactured by Mitsubishi Chemicals Corporation has low C1 errors and no C2 errors so it goes in the “Best Quality” category.

Editor’s note: This Verbatim CD-R media is Made in India.

Fujifilm media – manufactured by Daxon has low C1 errors and no C2 errors so it goes in the “Best Quality” category.

Writing Quality with CD-RW 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. All discs used for these tests are new and have not been written to before.

Verbatim media – manufactured by Mitsubishi Chemicals Corporation has high C1 so it goes in the “Poor Quality” category.

Sony media – made by Daxon has no C2 errors so it goes in the “Best Quality” category.

Summary:

The LG GGC-H20L is a very good CD-R writer showing excellent results with no C2 errors on our CD-R media and handled our CD-RW media (Sony) with good results; we would liked to have found our Verbatim Ultra High Speed 32X media to have done better.

But nevertheless, this is a Blu-ray Writer, so head on to next page and read about DVD-Writing performance and DVD media compatibility…

On the next page let’s take a look at the DVD+R/RW Writing Performance…