detail information

The specifications of this drive tell us that it should write DVD±R at 16x, DVD+RW at 8x, DVD-RW at 6x. In this part, we will measure the write time for various types of DVD+R/RW and DVD-R/RW discs. We will also focus on write quality and media compatibility.

DVD-Writing performance:

In this test we will measure the time for writing to DVD±R discs. We used Nero Burning Rom to burn an ISO compilation containing 4483Mb of data. We used the Disc-At-Once write method.

DVD+R

DVD-R

Look below for the results.

The Matshita DVD-RAM SW-9585 uses a Z-CLV write method but still competes quite nicely compared with what we see from other drives. Let us see how it performs in the writing quality department.

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 these tests we used a Lite-On SOHW-1693S and a Lite-On SOHW-1633S 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, PIF (Parity Inner Failures) set to summarize 1 ECC block, reading speed: 4X CLV (Constant Linear Velocity). Setting the PI sum to 8 and the PIF 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 are 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 below shows the results from a pressed, Single Layer DVD-Video disc (Ronin DVD).

This next scan shows the result from a pressed Double Layer DVD-Video disc (Lord of the Rings, The Return of the King). Notice the error jump when shifting to the second layer (the error levels actually drop 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 that 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 you're 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 PIF errors that K-Probe reports? They are Parity Inner Failures, meaning errors left after PI correction. Only the ECMA 337 standard describes the Parity Inner Failures. So how is a Parity Inner Failure defined? Here is what the 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 PIF since every ECC block is 208 rows long. But the ECMA 337 standard goes further and specifies the max amount of accepted PI Failures (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 PIF sum is set to 1, the maximum error value should not exceed 4. The theoretical maximum value for PIF is 208 errors.

But what makes a disc unreadable? A POF (Parity Outer Failure) error will make the disc unreadable, but K-Probe does not display the POF's.

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.

Also, 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 too 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 NEC 3500. A small speed reduction near the end is still accepted on good discs, but serious reading problems or reading failures is a bad sign.

In order to test the readability of the DVD±RW media, we use a BenQ 1640 or an NEC 3540A drive, which have higher speed reading capabilities for DVD±RW media.

An 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.

⋅         PIF (Parity Inner Failures): No larger areas on the disc should exceed 4 PIF-1 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; if it looks clean with no dips it should be good, a small slowdown near the end is accepted.

DVD+R media compatibility and write quality:

Before we enter into the DVD write quality testing, I would like to ask that we take a moment of silence for the finely crafted 16x certified medias that we are about to offer up to the Matshita DVD-RAM SW-9585. As you will see, the 16x write zone (Z-CLV) is seriously broken in the tested firmware.

It may have been a blessing that this disc was written at only 12x. The PI are elevated but the PIF turns out not so bad. The transfer graph looks ok.

As a side note to the 16x writing issues we used CD-DVD Speed to write a Verbatim 16x certified MCC004 at 12x for comparison. The burn only achieved 8x, but to illustrate that the problem truly lies with the 16x zone strats here is a scan of the ensuing burn. This shows the excellent quality of the media with the lower speed burn strategies.

This concludes our 16x certified media testing. Following are several 8x certified media and a single 4x certified media for good measure.

Excellent! Perfect reading curve! Best media available.

Another fine burn! Almost perfect reading curve.

This SONY D11 media burns fine and has an excellent read curve. Good media for this drive.

This is a very well written media and the read curve is flawless. Very nice!

This is a low cost store brand media that gives a decent result if you don't fill it to the edge. The read curve shows this.

Very nicely written, even if at slower than supported speed. Transfer graph is excellent.

Another fine burn, another fine transfer graph!

Nice burn on this low cost store brand. The only negative is a little hitch in the transfer rate graph near the end.

This was a very good burn until the outer rim, a nice read curve on this older 4x media.

DVD+ReWritable media:

The MATSHITA DVD-RAM SW-9585 should support writing to DVD+RW discs at 8x maximum. We tested with a Verbatim 8x DVD+RW disc made by Mitsubishi Kagaku Media.

The MATSHITA DVD-RAM SW-9585 writes to DVD+RW at 8x using Z-CLV (Zone-Constant Linear Velocity). The drive utilizes two zones to achieve an average writing speed of 7.09x and a total writing time of 8 minutes and 16 seconds on a full DVD+RW disc. Next we will analyze the writing quality.

The Kprobe graph shows some very high levels for PI errors and many unwanted PIF spikes. Thankfully the transfer rate graph is perfect. Panasonic could use some improvement in the writing quality area.

A very nice result. This quality burn produces an excellent read back curve.

Nice! There is a hitch in the read curve right at the end, but it is a good result overall.

High PIE/PIF totals but it produces a perfect read back curve.

DVD+R/RW Summary: The general write quality from the Matshita DVD-RAM SW-9585 was very good to excellent at 8x writing speed, however this drive just doesn't produce useable DVD+R burns at 16x speed. Panasonic is in serious need of correcting their 16x writing strategies on DVD+R discs! An option to burn 16x discs at 12x would also be a very welcome addition since the 12x zone appears to also write with good quality. The write quality on 4x DVD+RW was quite good overall, but the 8x DVD+RW writing quality could use some improvement.

Let's find out what it can do on DVD-R/RW media.

On the next page you will find the DVD-R/RW writing results...