Burn quality on different disc types

An introduction to disc quality checks.

At CD Freaks we see a lot of problems with standalone DVD recorders not accepting particular brands of blank DVD discs, or making recordings which are not compatible with DVD players. Reasons for the former can be explained by the tendency of some DVD recorder models to be picky about disc types, but also because of the higher speed ratings and recording dye types now marketed by the optical disc manufacturers. Reasons for the second group of problems can be due to poor quality of recordings or the failure of recorders to take advantage of built-in compatibility settings of <plus> format DVD discs.

Several general points are worth discussing here. The first is that DVD recorders without a hard disk have to write to DVD discs in real-time; effectively at 1x. But the majority of blank discs currently for sale are rated at least 8x and more likely 16x, and are designed to support the faster write speeds of computer optical drives. What is also problematic is the introduction of new recording dye types by the disc manufacturers, which have different light absorbances and reflectiveness that can be difficult for the recorder’s optical writing unit to accommodate. Essentially, this can cause difficulties with older standalone DVD recorders not recognising the media, or perhaps producing bad burns after not being able to assess the optimum writing strategy or laser power needed for a particular disc. This can be partly addressed with manufacturer’s firmware updates – which give the standalone recorder’s optical drive the necessary instructions on how best to write to newer media – but this does not help if you have just bought some new discs, where they aren’t recognised, and there isn’t a firmware update available. Also, inevitably there will eventually be a limit to how many new disc speeds and dye types can be effectively catered for by such updates.

To help deal with this potential problem, Philips has added a feature to the DVDR3480 called ‘SmartAlgo’. Presumably this is a means of either doing preliminary power calibration tests on an inserted disc, perhaps taking real-time feedback on burn quality whilst a recording is being made and retaining the information for subsequent recordings. Such capabilities are already found in utilities supplied by the manufacturers of computer optical drives, for example by BenQ and LiteOn (on-line hypertuning), and which allow the optimising of burn quality for different media types.

The Disc Quality tests…

Philips describes the DVDR3480 as supporting “dual media”: for which their definition is ‘DVD+R/RW, DVD-R/RW and DVD+R DL’. However the website, manual and specification sheets are confusing; in that sometimes –R DL discs are omitted, claimed to be read, or claimed to be written; depending on where you look. In order to sort it out we tried disc recordings on the DVDR3480 with all recordable DVD media types (except DVD-RAM).

The discs used were different dye types and speeds:

• single layer +R (two 8x and one 16x rated)
• single layer –R (two 8x rated)
• single layer +RW (one 4x and one 8x rated)
• single layer –RW (one 1-4x rated)
• double layer +R DL (one 4x rated)
• double-layer –R DL (one 4x and one 8x rated)

All recordings were made at HQ setting of the DVDR3480, finalised on the unit, and scanned between one and seven days later in a PC optical drive under the simple criteria according to those recommended in the CD Freaks’ Home Scanning article.  Briefly, for scanning all the discs we used CD-DVD Speed version 4.07 with a LiteOn SHW-16H5S (firmware LV4D).

One table and two graphs are displayed for each disc: the table is the basic disc information including manufacturer’s media identity (MID); and the two graphs are the ‘Disc Quality Scan’ and the ‘Transfer Rate’ test. The former looks at the surface of the disc at a constant speed and measures detectable (yet correctable) errors in the recording. The transfer rate test pushes the error correction system of the drive up to a high speed limit and sees how well those errors on the disc can still be corrected under such ‘stress’.

The results and general comments are shown below, but for the detailed interpretation of these you should read in full the CD Freaks’ Home Scanning article.

DVD+R media ID: CMC MAG E01 (rated 8x speed)

Disc Quality scan:

Transfer Rate test:

Disc quality scan: Good figure of max PI error 22 (should be less than 280), and although most PI failures are less than 4, there are some at 5 and a max of 6 is a little high (ideally should be no higher than 4 except perhaps with a single spike).

Transfer rate test: excellent with no measurable drop in data transfer all the way up to 12x speed.

Preliminary conclusion: Great burn on an 8x-rated disc.

Note: From the disc info table it’s clear that the DVDR3480 is automatically book-typing the +R disc to DVD-ROM for maximum compatibility in other DVD players.

DVD+R media ID: YUDEN000 T02 (rated 8x speed)

Disc Quality scan:

Transfer rate test:

Disc quality scan: nice low PI error max of 14 (remember this should be less than 280). PI failures mostly 4 or less but a max of 6 right at the end of the disc can probably be ignored.

Transfer rate test: Perfect results with no slowdowns whilst reading up to 12x speed.

Preliminary conclusion: Good burn on an 8x-rated disc.

Note: Same book-typing of +R to DVD-ROM for compatibility

DVD+R media ID: YUDEN000 T03 (rated 16x speed)

Disc quality scan:

Transfer rate test:

Disc quality scan: very low PI error max of 15. PI failures mostly 4 or less but rises slightly towards the end of the disc.

Transfer rate test: Very good results, but just the slightest suggestion of a slow-down at the 3.6 GB and 3.85 GB marks. However note the faster speed of the transfer rate test performed on this disc; the blips occurred at about 15x speed.

Preliminary conclusion: Very good burn on a 16x-rated media type.

Note: Same booktyping of +R to DVD-ROM for compatibility.

DVD-R media ID: MCC 02RG20 (rated 8x speed)

Disc Quality scan:

Transfer Rate test:

Disc quality scan: nice low PI error max of 19. PI failures all 4 or less.

Transfer rate test: Perfect results with no slowdowns whilst reading up to 12x speed.

Preliminary conclusion: Excellent burn on an 8x-rated –R disc.

Notes: Interestingly the chipset responsible for the recording is revealed in this set of tests as being MTK DVDR MT1858. We’ll comment on this later.

DVD-R media ID: CMC MAG AE1 (rated 8x speed)

Disc Quality scan:

Transfer Rate test:

Disc quality scan: relatively very low PI error max of 21. PI failures all 4 or less except for a couple of spikes towards the end.

Transfer rate test: Perfect results with no slowdowns whilst reading up to 12x speed.

Preliminary conclusion: Excellent burn on an 8x-rated –R disc.

DVD+RW media ID: MKM A02 (rated 1-4x speed)

Disc Quality scan:

Transfer Rate test:

Disc quality scan: Good figure of max PI error of 27, and although most PI failures are less than 4, there are some spikes up to 5 and a max of 7.

Transfer rate test: excellent with no measurable drop in data transfer all the way up to 12x speed.

Preliminary conclusion: impressive results for a +RW, which characteristically tend to show higher errors than write-once media

Note: The DVDR3480 is NOT automatically book-typing the +RW disc to DVD-ROM.

DVD+RW media ID: MKM A03 (rated 8x speed)

Disc Quality scan:

Transfer rate test:

Disc quality scan: Very low PIE figure of 21 and exceptionally low PIF max of 3.

Transfer rate test: Perfect readback curve all the way up to 12x speed.

Preliminary conclusion: Excellent burn on a fast-rated +RW disc.

DVD-RW media ID: MCC 01RW4X (rated 4x speed)

Disc quality scan: Exceptionally low PIE figure of 12 and PIF max of 3.

Transfer rate test: Perfect readback curve all the way up to 12x speed.

Preliminary conclusion: Truly excellent burn on a -RW disc.

DVD+R DL media ID: MKM 001 (rated 4x speed)

Disc Quality scan:

Transfer Rate test:

Disc quality scan: Very low PI error rate until the layer change, when a large jump in reported errors occurs to a max of 272 (remember the ideal maximum of 280). Nevertheless the PI failure rate is exceptionally good; with nothing above 3 except for a single orange spike of 6 right at the end (which can probably be ignored as a scan artefact).

Transfer rate test: Excellent with no significant drop in data transfer across both layers, all the way up to 8x speed and back (the very slight fall at the layer break just before the 4 GB mark can be ignored).

Preliminary conclusion: Excellent results on this double-layer media. The significant jump in PI error rate can be mostly explained by the lower reflectivity of the second recording layer.

Note: The DVDR3480 is automatically book-typing the +R DL disc to DVD-ROM for compatibility.

DVD-R DL media ID: MKM 01RD30 (rated as 4x speed)

Disc Quality scan:

Transfer Rate test:

Disc quality scan: Extremely good burn for a dual layer disc (PIE of 33 and PIF of 3). Note the absence of a jump in PI errors after the layer change (compare it with the +R DL DQ scan above).

Transfer rate test: Perfect reading curve with no drive slowdowns.

Preliminary conclusion: One of the best burns in this review.

DVD+R DL media ID: MKM 03RD30 (rated as 8x speed)

Disc Quality scan:

Transfer Rate test:

Disc quality scan: Another very good burn for a dual layer disc (PIE of 23 and PIF of 3). Perhaps a suggestion of an increase in PI errors after the layer change but hardly noticeable.

Transfer rate test: Perfect reading curve with no drive slowdowns.

Preliminary conclusion: Another great DL burn.

Verdict on disc quality

We have shown from the above results how well the burn engine of the DVDR3480 records on a variety of blank media (physical construction, number of layers, dye types, and speed ratings). By keeping two factors constant – the recording device and the scanning drive - we would expect the observed PIE and PIF differences between discs to more likely reflect the quality of the burn on those particular media types.

Leaving aside these analytical restrictions, we chose a real-world premise for these tests. Most of these blank discs had been sitting around for several months (some over a year) in cake-boxes in a domestic environment, and moreover, we did the scanning on most of them a week after the recording was made. Thus although we took care to analyse the results carefully, the discs were chosen in keeping with how the recording situation might occur in real life.

Based on our limited testing parameters and results presented above, we can say that whatever the basic physical disc format; any of the single-layer write-once or rewriteable, or even the double layer disc types will be suitable for using in the DVDR3480. They all have slightly different recording/scanning characteristics but in our opinion there is not a bad burn among them. If we had a preference purely on burn quality alone then it would be the 8x rated –R 02RG20 for single layer write-once, the 4x -RW MCC 01RW4X for rewriteable, and for double layer; the 4x –R DL MKM 01RD30. However this is by no means the whole story, and the playback compatibility of these disc types in other standalone dedicated DVD players is also of importance. For example it is not possible to book-type the –R or –RW discs to DVD-ROM, yet some older DVD players may need this.

Scanning the recordings made on the –R format discs revealed the chipset used in the DVDR3480 as being a DVDR version of the MediaTek MT1858. This is of a family of devices that have recently been introduced with remarkable success into PC-based DVD rewriters; such as the LiteOn DH20A3, the Samsung 20x series, and the Sony DRU-840A amongst others. In particular the MT1858 series produces comparatively low jitter results when burning at low speed; which is an important factor in considering consistent video playback. Also we must remember that Philips and LiteOn are now collaborating (through their declared association as ‘Philips & LiteOn Digital Solutions Corp’ – PLDS), and so we would speculate that the hardware inside the DVDR3480 may well resemble a stock LiteOn PC unit.

Basic operation & recording

Technical encoding quality