Disc Quality tests
Having recorded the maximum amount possible onto the Traxdata 16x DVD-R media at its rated recording speed of 16x to our review drives with CD Speed, the next stage of our review will concentrate on Disc Quality.
Now normally it is here where we would show you the Disc Quality scans using CDSpeed or KProbe with a Liteon writer such as the 1673S, or the BenQ DW 1620A. But now in a new revised 2 stage Disc Quality structure we can offer what we believe to be the most indepth look at the various effects and that we can build a better picture of potential quality with any given Media/Hardware/Speed combination. It has taken 3 months and over 300 various DVD tests to come up with this new structure so we believe it has been tested fully and holds up well.
"As the whole purpose of reviewing media for our readers is to try and obtain a good idea of the average quality of a given media, we have come up with this new methodoligy for determing these factors. These are our own personal views and by no means as accurate as an Industry CAT scanner for measuring the quality of a disc but we believe we have come as close as we possible can do with the equipment available to the average user."
The first part of our Quality tests involved scanning all the pieces of Traxdata 16x DVD-R media recorded on each review recording device with our Liteon 1673S with Kprobe to find out how many potential PI error and PI Failures a playback device would have to correct whilst playing or transferring the recorded media. This also enabled us to obtain which of the 5 recorded pieces of media most matched the average result based on the well accepted method of PIE/PIF scanning on the Liteon 1673S to show in this stage of the review.
Sounds like a lot to read but basically in our new 2 tier Disc Quality structure here is a brief explanation of what each test can tell us:
The PIE and PIF results show us how many potential errors a playback device may need to correct.
The beta and jitter tests tell us how well balanced a recording is at any given speed.
The TA and peak shift tests tell us how well the actual recording pit of the media has been produced at 3 measured stages during the recording.
"We thank both Karr for his excellent free KProbe software and Alex Noe for his very informative website and very useful PXScan software on behalf of ourselves and any readers that may benefit from the information provided by his Free software. PXScan enables us to do all our required tests in one run and display all the results in one easy to read graph. Without it we would have to show you several different screenshots instead of one for each drive when doing the advanced tests in the Plextor PX-716A."
Results of these tests are shown below:
But that only allows us to see the amount of potential PIE/PIF errors that may need to be corrected by any given DVD playback device. Now we can further examine the average result using the Plextor PX-716A and the excellent PXScan. With this combination of the Plextor and PXScan we can show you even more detailed information about other potential issues that may have to be corrected by playback and transfer devices such as jitter/beta/TA and peakshift.
The Plextor results may look a little hard to understand at first but if like us you take the time to have a good read of the well explained information on the PXScan Website, it will become clear just how these tests work but briefly here are what the new tests can tell us.
Shown below are the results of the PXScan tests:
Overview of Disc Quality results:
The Disc Quality results show that the recordings achieved to all review recording devices where of a very good standard. Where 16x was supported, again the results look as good, if not better than the 12x results we achieved on drives which did not support the manufacturers maximum rated recording speed. The potential PIE and PIF errors reported by the Liteon 1673S under firmware JS0C where within set limits and the PIF errors where very low on all drives tested during this review. Towards the end of the recording, according to PXScan the recorded pits did start to show a small lean and the Peak shift was slightly off center on some recordings, but both the Plextor PX-716A and BenQ DW 1640 for example handled this media very well.
"Please note that you will need a compatible drive for doing these scans such as the Plextor PX-716A and Liteon-IT 1693S we have used in this review for making our decisions on the potential quality of this media. Other drives you could try include BenQ, NU TECH and ASUS branded writers, but only the Plextor PX-716 offers the full range of tests."
The less PI/PIF errors that are found on a media then in theory the better the chances are of good long term playback for this media without data loss becoming a problem. Different scanning devices scan slightly differently but basic guidelines using either a Plextor or Liteon drive are that PI errors should not exceed 280 for sustained periods and PI failures should not exceed 4 for sustained periods. Jitter and beta must remain within set specifications for a Plextor scan ( these will highlighted red in the Disc Quality results if they exceed limits and we would like to see a well written and uniform recording 'pit' during the TA tests for an optimal result at any given speed.
We will expect that not every piece of media is capable of producing this
with such influences as excepted media/ hardware tolerance levels having an impact but we will expect the results not to consistently stray too far from set standards for a recommended media.
If using a Liteon Writer to scan for Pi error and PI failure levels single spikes are usually ignorable due to a bug in the Liteons Mediatek chipset but we will confirm the readability if the recordings with our transfer tests."
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