Disc Quality Tests
Having recorded the maximum amount possible onto the Miflop 16x DVD+R media at its rated recording speed of 16x to all available review drives with Nero CD-DVD Speed, the next stage of this review will concentrate on Disc Quality.
The first part of the Quality tests involved scanning all the pieces of Miflop 16x DVD+R media recorded on each review recording device with the Plextor PX-755A using Plextools Q-Check tests to find out how many potential SUM8 (PI Errors) and Sum1 (PI Failures) a playback device would have to correct whilst playing or transferring the recorded media. This also enabled me to obtain which of the 5 recorded pieces of media used in this review most matched the average result. The average disc shown below was then subjected to a Beta and Jitter test. Although more tests are available I believe I am showing the most common factors in overall disc quality.
"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, I have come up with this new methodoligy for determing these factors. These are my own personal views and by no means as accurate as an Industry C.A.T.S scan for measuring the quality of a disc but I believe I have come as close as I possibly can do with the equipment available to the average user."
I 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 I will expect the results not to consistently stray too far from set standards for a recommended media. It is also the sum of all tests that I use to determine the overall quality of the media and not one test alone.
The less Sum1 and Sum8 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 significant problem. Thats not to say that recordings with high Sum1 and Sum8 levels will be bad - the error correction logic of DVD playback and transfer devices are capable of correcting many potential errors. There is just more chance they might be affected by such influences as dirt or fingerprints. Different scanning devices scan slightly differently but basic guidelines using a Plextor drive are that Sum8 should not exceed 280 for sustained periods and Sum1 should not exceed 4 for sustained periods. You don't want to see any reported POF's (Parity Outer Failures) as these normally should result in uncorrectable errors!
Jitter and beta must remain within set specifications for a Plextor scan (Beta should not exceed +15 or -5 for sustained periods with the more level the result the better). Jitter should stay within the lower half of the graph for best results. Reading devices with good jitter correction ability should be able to read higher reported levels better than those that don't.
Overview of Disc Quality results:
With all used review recording devices having reached the rated speed of 16x for this media for every single disc tested, my expectations for a decent quality result was very high. But as reported in the Plextor 16x DVD+R media review which uses the same dye as the Miflop media, early batches had shown higher than expected Sum1 and Sum8 levels for a Taiyo Yuden based media ( and I suspect most knowledgable burners would agree with this statement ). With this newer batch of Miflop 16x DVD+R media, reported Sum1 and Sum8 levels are significantly lower and less concentrated. Infact its fair to say that results shown in this part of the review are close to matching expectations for a Taiyo Yuden based media.
The LG GSA-4166B, and Philips DVDR1660P1 led the way with very good and even results reported in the Q-Check tests for both writers. The Plextor PX-755A and Pioneer DVR 110 also offered an excellent level of support and very good results. As noted in the Philips 16x DVD+R media review, the NEC ND-4551A recording reported high levels of sum8 right at the end of the recording but Sum1 and Beta/jitter levels achieved decent results.
As Sum8 errors are the least important of any of the tests I wouldn't worry too much about them but an 'In Spec' Q-Check result is always preferred.
Please note that you will need a compatible drive for doing these scans such as the Plextor PX-755A I have used in this review for making my decisions on the potential quality of this media. Other drives you could try include BenQ, Liteon, NU TECH and ASUS branded writers, but only the Plextor drives with Q check functions offer the full range of tests.
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