detail information

DVD-Writing performance:

In this test we will measure the time for writing a DVD+R disc at 16x. We used Nero burning Rom to set up a new UDF/ISO compilation containing 4483Mb of data, and started the write process. We used the Disc-At-Once write method. For reference we will again include tests from the BenQ DW822A.

BenQ DW1600A writing at 16x.

BenQ DW822A writing at 8x.

Again there is a bit over 2 minutes in difference; to be exact there is two minutes and 10 seconds in difference. Let us take a look at writing quality at 16x.

Write quality:

You should first notice that this is not a scientific and professional way to test the discs. But according to our testing done in recent months, we would conclude that there is a clear link between the quality reported when scanning the disc and the playability of the disc in different devices. Also notice that different drives report different amounts of errors. K-Probe was designed to work with Lite-On DVD-Writers. So we recommend using a DVD-Writer from Lite-On, in this test we use a Lite-On SOHW-832S DVD-Writer, as already said; remember that scans done with a Lite-On DVD-ROM or Lite-On combo drive can't be compared with the results obtained with a Lite-On DVD-Writer. Also remember that different PI/PO ECC sum settings along with different reading speeds in K-Probe will affect the result, we use these settings;  PI (Parity Inner) set to summarize 8 ECC blocks, PO (Parity Outer) set to summarize 1 ECC block, reading speed: 4X CLV (Constant Linear Velocity). Setting the PI sum to 8 and the PO sum to 1 will give a result that we may compare to the standards for DVD+R/RW and DVD-R/RW.

But what is a good scan? That is a discussion that we don't think will end soon, as different drives report different amount of errors, some players is more picky about media than others, and so on. But as a comparison we present you with a scan from two pressed DVD discs:

This scan shows the results from a pressed DVD-ROM disc (Baldurs Gate DVD-ROM).

This scan shows the result from a pressed DVD-Video disk (Indiana Jones and the last crusade). Notice the error jump when shifting to the second layer (the error level actually drops from the end of the first layer to the beginning of the second layer).

If you read below you will see that both the pressed DVD-discs are well within the standards.

Download the ECMA 267 Standard for DVD-ROM, the ECMA 337 Standard for DVD+R/RW and the ECMA 338 Standard for DVD-R/RW at http://www.ecma-international.org if you want to look at the standards for yourself. Here is some data from the ECMA standards (same for DVD-ROM, DVD-R/RW and DVD+R/RW):

Random errors:

A row of an ECC Block that has at least 1 byte in error constitutes a PI error. In any 8
consecutive ECC Blocks the total number of PI errors before correction shall not exceed 280.

Here we see what a PI error is defined as a row in an ECC block having 1 byte or more containing errors. And that the sum of PI errors in 8 ECC blocks after each other should not exceed 280 PI errors.

But what is a row and what is an ECC block? Again we refer to the ECMA standards. We do not copy and paste everything but if interested look in the ECMA standards. A row is 182 bytes long where the last 10 bytes contain PI (Parity Inner) information. An ECC block is 208 rows long where the last 16 rows contain the PO (Parity Outer) information. This gives us a maximum possible PI error amount of 208 errors per block and for 8 blocks after each other this sum is of course 8 times higher giving a maximum possible amount of 1664 PI-8 errors. In practical use a disc with 1664 PI-8 errors is unreadable.

According to our tests the specified max PI-8 sum of 280 for good discs seems to be a good guideline, as some readers have problems reading discs when the PI-8 errors is over 300 and most players starts to have problems when the PI-8 error level reaches 600 or more.

But what are the PO errors that K-Probe reports? Actually the PO errors that K-Probe reports is the Parity Inner uncorrectable errors, meaning errors left after PI correction. Only the ECMA 337 standard describes the Parity Inner uncorrectable errors. So how is a Parity Inner uncorrectable error defined? Here are what ECMA 337 states:

'If a row of an ECC Block as defined in 13.3 contains more than 5 erroneous bytes, the row is said to be 'PI-uncorrectable"."

In theory an ECC block may in the worst case have 208 PI uncorrectable errors since every ECC block is 208 rows long. But the ECMA 337 standard goes further and specifies the max amount of accepted PI uncorrectable errors allowed on a good disc:

'- In any ECC Block the number of PI-uncorrectable rows should not exceed 4."  

This means that when the PO sum is set to 1 the maximum error value should not exceed 4. The theoretical maximum value for PO errors is 208 errors.

But what makes a disc unreadable? A PO uncorrectable error will make the disc unreadable, but K-Probe does not display the PO uncorrectable errors.

Notice that there are other aspects such as disc reflectivity, jitter, tracking errors and so on that also will affect the readability of a DVD disc '� but for this we do not have measuring equipment available.

And another note is that we have scanned the discs at 4X CLV speed, by lowering the speed to 2X(DVD-R/RW)/2.4X(DVD+R/RW) or 1X the amount of reported errors may drop on some discs. We scanned at 4X CLV due to lower speeds taking to much time.

To see if there is a connection between the reported amount of errors and readability of the discs we also include the reading curve from a JLMS XJ-HD165H DVD-ROM that seems to be pretty easy affected by the quality of a written disc.

Easier explanation on how to read the test results.

Maybe this got too technical, and you are wondering what to look for in Kprobe reports?

Use this as a guideline for good discs:

PI(Parity Inner): No larger areas on the disc should exceed 280 PI-8 errors, do not worry too much about high single spikes that exceed 280.
PO (Parity Outer): No larger areas on the disc should exceed 4 PO-1 (actually PI uncorrectable) errors, do not worry too much about high single spikes that exceed 4.

And as always; lower is better ;)

And look at the reading curve, a slight slowdown at the end is probably nothing to worry about, but huge bumps and slowdowns are not good.

16x writing quality:

Let us start with taking a look at the media information of the 16x Philips media that BenQ shipped us, for this we will use DVD-Identifier 3.3.

--------------------------------------------------------------------------
Unique Disc Identifier : [DVD+R: PHILIPS-C16-000]
--------------------------------------------------------------------------
Disc Type :              [DVD+R]
Manufacturer ID :        [PHILIPS]
Manufacturer Name :      [Philips]
Media Type ID :          [C16]
Product Revision :       [Not Specified]
Disc Application Code :  [General Purpose]
Recording Speeds :       [1x , 2.4x , 4x , 6x-8x , EI2x]
Blank Disc Capacity :    [2,295,104 Sectors = 4,482.6 MB = 4.38 GB]
--------------------------------------------------------------------------
[DVD Identifier - http://DVD.Identifier.CDfreaks.com]
--------------------------------------------------------------------------

DVD-Identifier is not updated to support 16x media yet and it returns the following error message:

[19:49:51] Unknown EI-Block Has Been Detected (EIx)
[19:49:51] An Upgrade Of 'DVD Identifier' Is Recommended

This is since 16x media is not finalized yet, and thus DVD-Identifier is unable to know what speed it's certified for.

Here is the full media code:

0000 : 00 00 00 00 a1 0f 02 00  00 03 00 00 00 26 05 3f   .............&.?
0010 : 00 00 00 00 00 00 07 50  48 49 4c 49 50 53 00 43   .......PHILIPS.C
0020 : 31 36 00 38 23 54 37 12  02 74 6a 02 c0 67 16 15   16.8#T7..tj..g..
0030 : 0b 0b 08 08 01 19 1b 0c  0c 0c 0d 01 00 00 00 00   ................
0040 : 00 00 00 00 01 00 38 38  02 35 61 16 08 2e 23 10   ......88.5a...#.
0050 : 04 1e 1d 01 00 00 02 35  61 16 08 2e 23 10 04 1e   .......5a...#...
0060 : 1d 01 00 00 02 00 54 70  02 43 00 42 20 14 0a 0a   ......Tp.C.B ...
0070 : 01 18 00 00 00 00 02 46  00 7a 20 14 0a 0a 01 18   .......F.z .....
0080 : 00 00 00 10 03 00 54 e0  02 43 00 42 20 14 0a 0a   ......T..C.B ...
0090 : 01 18 00 00 00 00 02 93  00 3e 2c 18 0c 0c 01 20   .........>,....
00a0 : 00 00 00 a2 00 00 00 00  00 00 00 00 00 00 00 00   ................

 And here is the K-Probe result as well as a reading curve from our JLMS XJ-HD165H DVD-ROM:

The result is pretty good, but not perfect as the reading curve shows. But the result is still more than good enough to not cause any problems in practical use. As a second test we used Plextools Q-Check to test the disc as well, we used the SUM1 test.

When using the SUM 1 test the maximum allowed error value is 4 for a disc to be within specifications, you could see there is as a darker line on the image reflecting the maximum error value. And there were a few spikes exceeding this limit so the disc is not perfect as already mentioned, but again it will probably be more than good enough to not cause any problems in practical use. Let us try the included Taiyo Yuden 8x disc at 16x speed, first let us look at the media information:

--------------------------------------------------------------------------
Unique Disc Identifier : [DVD+R:YUDEN000-T02-000]
--------------------------------------------------------------------------
Disc Type :              [DVD+R]
Manufacturer ID :        [YUDEN000]
Manufacturer Name :      [Manufacturer ID Not Found In Database]
Media Type ID :          [T02]
Product Revision :       [Not Specified]
Disc Application Code :  [General Purpose]
Recording Speeds :       [1x , 2.4x , 4x , 6x-8x]
Blank Disc Capacity :    [2,295,104 Sectors = 4,482.6 MB = 4.38 GB]
--------------------------------------------------------------------------
[DVD Identifier - http://DVD.Identifier.CDfreaks.com]
--------------------------------------------------------------------------

Full media code:

0000 : 00 00 00 00 a1 0f 02 00  00 03 00 00 00 26 05 3f   .............&.?
0010 : 00 00 00 00 00 00 03 59  55 44 45 4e 30 30 30 54   .......YUDEN000T
0020 : 30 32 00 38 23 54 37 10  02 4e 72 02 8c 63 16 16   02.8#T7..Nr..c..
0030 : 0b 0b 0a 0a 01 19 1b 0c  0c 0c 0d 01 00 00 00 00   ................
0040 : 00 00 00 00 01 00 38 38  02 34 63 13 05 22 22 10   ......88.4c.."".
0050 : 0e 12 12 01 00 00 02 34  63 13 05 22 22 10 0e 12   .......4c..""...
0060 : 12 01 00 00 02 00 54 70  02 4e 64 4a 20 11 08 08   ......Tp.NdJ ...
0070 : 01 18 00 00 00 00 02 67  64 4e 20 10 08 08 01 18   .......gdN .....
0080 : 00 00 00 30 00 00 00 00  00 00 00 00 00 00 00 00   ...0............

And here are the results:

The result is great, until near the end where it increases quickly and makes the disc unreadable. Does this mean that 16x media is required to get good results at 16x? Time will show as there is still no finished 16x writers available. Some firmware adjusting may make wonders '� and it may not, we will have to wait to find out. Again let us try Q-Check SUM1 test:

The Q-Check test just verified our results; the red area at the end reflects the uncorrectable errors that made the disc unreadable.

To see what speeds 8x certified discs are supported at we include the following table:

*Seems to not be added in the firmware and thus defaults to 16x, which those two media types can't handle of course '� they even have problems at 8x speed in most drives and sure enough, the Walking OPC technology slowed the speed down to 4x for both these media types while trying to write to them.

Ricoh and Philips 8x media were supported at 12x speed, the rest are supported at 8x speed only. That was all for now, lets sum it up below

Summary:

BenQ is the first to have a drive capable of writing at 16x DVD+R speed, which they deserve credit for of course. And unlike some other manufacturers they did also go the official route and dropped the 12x speed which is outside the specifications of DVD+R. But then we have media, 16x DVD+R media will most likely not hit market anytime soon. Could we guess that 16x media will start to become available in stores Near Christmas this year? For most of the world the answer will probably be yes as very few media manufacturers have announced 16x media yet. But it seems like drive manufacturers will not wait for 16x media to arrive, so how will they get around this? Most likely by supporting one or two types of 8x media at 16x speed. Is this a good and working solution? In this preview it appears to not be a good solution as the Taiyo Yuden 8x DVD+R ended up unreadable at the end when written at 16x, this may and probably will improve as drives and firmware gets fine tuned. Remember that we are still speaking about an early test

But from BenQ's point of view it's a good idea to release a 16x model since this is the correct way to go according to the DVD+R specifications and they will have a 'mine is bigger than yours" effect on drives from manufacturers only releasing outside specifications 12x writers. When the average user visits the stores/browsing a web shop he/she is normally looking for the largest number for the lowest price, so if there is a 16x and a 12x drive side by side and the price do not differ too much, then odds are large that the 16x model would be picked, unless the buyer looks for a special brand.

Well, now you've seen the first 16x DVD-Writing tests, but they will for sure not be the last as many manufacturers are readying their 16x models. Lite-On, NU tech and Artec is just some. You know where you will always find the latest news about the latest drives; right here at www.cdfreaks.com and at our huge forum; http://club.cdfreaks.com where thousands of users from the whole world shares their own experience with new products.

You may discuss/comment this article below or in this forum thread.

The drive and specifications

Conclusion