Sony BWU500S Review
22. BDR burning  Panasonic BDR SL 6x (MEI RA1)
Review Pages
2. CD, DVD and Bluray Disc reading tests
3. CD Error Correction tests
4. DVD Error Correction tests
5. CD/DVD writing quality testing platform
6. CDR burning  TDK (Ritek) CDR 48x
7. CDR burning  Taiyo Yuden CDR 48x
8. CDRW burning  Verbatim CDRW 32x
9. DVDR burning  Ricoh (CMCMAG AM3) DVDR SL 16x
10. DVDR burning  Verbatim (MCC03RG20) DVDR SL 16x
11. DVDR burning  Ridisc (TTH02) DVDR SL 16x
12. DVDR burning  Taiyo Yuden (TYGO3) DVDR SL 16x
13. DVDRW burning  TDK (CMCW04) DVDRW 6x
14. DVDR DL burning  Verbatim (MKM03RD30) DVDR DL 8x
15. DVD+R burning  Philips (INFOME R30) DVD+R 16x
16. DVD+R burning  Moser Baer India (MBIPG101R05) DVD+R 16x
17. DVD+R burning  Verbatim (MCC004) DVD+R 16x
18. DVD+R burning  Datawrite Titanium (PRODISC R04) DVD+R SL 16x
19. DVD+RW burning  Verbatim (MKMA03) DVD+RW 8x
20. DVD+R DL burning  Verbatim (MKM003) DVD+R DL 8x
21. DVDRAM burning  Maxell DVDRAM 5x, 12x
22. BDR burning  Panasonic BDR SL 6x (MEI RA1)
23. BDR burning  Sony BDR SL 6x (SONY NN3)
24. BDR burning  Verbatim BDR SL 6x LTH (VERBATIMu)
25. BDR Burning  Moser Baer BDR SL 6x (MBI R06)
26. BDR burning  Verbatim BDR SL 6x (VERBATIMe)
27. BDR burning Verbatim BDR SL 7.5GB 2x (VERBATIMa)
28. BDR DL burning  Panasonic BDR DL 6X (MEI RB1)
29. BDR DL burning  Verbatim BDR DL 6X (VERBATIMf)
30. BDR DL burning  TDK BDR DL 4x (TDKBLDRFB)
31. BDR DL burning  Verbatim BDR DL 2x (VERBATIMb)
32. BDRE burning  Verbatim BDRE SL 2X (VERBATIM0)
33. BDRE DL burning  BDRE DL 2x (VERBATIM1)
34. BDRE DL burning TDK BDRE DL 2X (TDKBLDWfa)
35. Summary of DVD, BD quality tests, Overburning, Booktype
36. Final words
From this page and for the following we start our Bluray disc tests with the Sony BWU500S drive. We remind you that the drive supports 12x BDR SL and 8x BDR DL recording with specific media certified for 6x recording. For firmware v1.63, the supported media list includes:
Sony BWU500S v1.63 
Write Speed 
Disc Maker 
Media speed 
Manufacture ID 
Disc Type ID 
BDR 
Max write speed 12X 
Panasonic 
6x 
MEI 
RA1 
Sony 
6x 
SONY 
NN3 

Ritek 
6x 
RITEK 
BR3 

Max write speed 6X 
TDK 
6x 
TDKBLD 
RBD 

MKM 
6x 
VERBAT 
IMe 

MBI 
6x 
MBI 
R06 

BDR DL 
Max write speed 8X 
Panasonic 
6x 
MEI 
RB1 
Sony 
6x 
MEI 
RB1 

Max write speed 6X 
TDK 
6x 
TDKBLD 
RFD 

MKM 
6x 
VERBAT 
IMf 
Of course, any other BD discs will be burned at speeds up to 4X.
We also used Erik Deppe' s Opti Drive Control software for testing the writing quality of each recorded BDR/RE disc. The software could give you an idea of the writing quality of each disc. For BDs, the following parameters are measured:
 LDC (Long Distance Code): number of parity errors on LDC codewords per ECC block (32 sectors)
 BIS (Burst Indication Subcode): number of parity errors on BIS codewords per ECC block (32 sectors)
On a good disc, the average LDC should stay below 13 and BIS should stay below 15, according to the author of the software.
If you are interested in the data recovery methods of the Bluray discs, continue reading below. If not, skip the following text and proceed directly to the tests found later on this page :)
Bluray Data Recovery Methods: Partial Response  Maximum Likelihood (PRML)
For CD and DVD, the method for data detection was based on a zero crossing point method, using a conventional slicer. Basically, when the analogue signal (output from the optical pickup) crosses a reference level, it indicates a binary transition. This method has its limitations, notably when the feature size (smallest pit/land) is less than the spot size, the modulation of the light is relatively small (the smaller the pit/spot size ratio the smaller the modulation). Thus, the conventional slicer can create data with nonexact mark/space lengths  otherwise known as jitter, and when this jitter becomes greater than 0.5 of a clock cycle, it becomes a bit error.
For BD, the minimum spot radius ratios are 0.88 and 0.85 of the ratio of DVD. This reduced resolution (low modulation of light by 2T pits) means that it is much more difficult to have effective data detection using a conventional slicer. Boosting the high frequency part of the signal has limited effect because this also increases the InterSymbol Interference (ISI), which is where adjacent pits and lands interfere with each other. This is mainly a problem with the shortest run lengths, particularly those that are smaller than the spot size.
Hence for BD, the Partial Response Maximum likelihood (PRML) method is used for recovering the data from the signal.
Partial Response (PR) equalization is used to limit the effects of ISI, and then a sequence of bits is evaluated to define the most likely sequence of bits, based upon known allowed sequences. This is the Maximum Likelihood (ML) detection and uses a Viterbi algorithm to determine the ML sequence.
The BluRay disc is more sensitive to burst errors compared to the DVD system. Therefore, the error correction system of BluRay disc should be able to cope well with long burst errors, rather with single (random) errors.
The maximum number of errors that can be corrected depends on the number of parity symbols added. For each two parity symbols added, one error can be corrected. But BluRay uses a more efficient approach to correct the burst errors. It uses a burst indicator mechanism that can detect bursts of errors before the correction starts. The advantage of this method is actually the prior knowledge of the error locations on the decoding process.
These burst indicator used in the BluRay format is called picket code. The pickets are columns that are inserted in between columns of the main data at regular intervals. The main data is protected by a Reed Solomon code, while the pickets are protected by a second independent Reed Solomon code. When decoding (reading), first the picket columns are corrected. The correction information can be used to estimate the location of possible burst errors in the main data.
A BluRay Disc Error Correction Block (ECC Block) can store 64 Kilobytes of user data. This data is protected by the Long Distance Code (LDC) which has 304 code words with 216 information symbols and 32 parity symbols giving a code word of length 248. These code words are interleaved two by two in the vertical direction such that a block if 152 bytes x 469 bytes is formed as shown in the picture above.
A BluRay Disc ECC block contains 4 equally spaced picket columns. The left most picket is formed by the sync pattern at the start of each row. If the sync pattern was not detected properly, that can be an indication for a burst error similar to the knowledge that a symbol of a picket column had to be corrected. The other three pickets are protected by the socalled Burst Indicator Subcode (BIS). The BIS code words are interleaved into three columns of 496 bytes each. Both LDC and BIS codes are decoded by the Reed Solomon decoder.
Reference: BDROM Physical Specifications
 Media Info Panasonic BDR SL for 6x (MEI RA1)
 Writing 12X CAV (8.96Xx average) in 11:39 min
 Quality
This time the average LDC was higher 13. Both the LDC and the BIC rise after the 17.5GB mark of the disc and towards the end of the data area, as the recording speed was also increasing to reach the maximum 12x.
Review Pages
2. CD, DVD and Bluray Disc reading tests
3. CD Error Correction tests
4. DVD Error Correction tests
5. CD/DVD writing quality testing platform
6. CDR burning  TDK (Ritek) CDR 48x
7. CDR burning  Taiyo Yuden CDR 48x
8. CDRW burning  Verbatim CDRW 32x
9. DVDR burning  Ricoh (CMCMAG AM3) DVDR SL 16x
10. DVDR burning  Verbatim (MCC03RG20) DVDR SL 16x
11. DVDR burning  Ridisc (TTH02) DVDR SL 16x
12. DVDR burning  Taiyo Yuden (TYGO3) DVDR SL 16x
13. DVDRW burning  TDK (CMCW04) DVDRW 6x
14. DVDR DL burning  Verbatim (MKM03RD30) DVDR DL 8x
15. DVD+R burning  Philips (INFOME R30) DVD+R 16x
16. DVD+R burning  Moser Baer India (MBIPG101R05) DVD+R 16x
17. DVD+R burning  Verbatim (MCC004) DVD+R 16x
18. DVD+R burning  Datawrite Titanium (PRODISC R04) DVD+R SL 16x
19. DVD+RW burning  Verbatim (MKMA03) DVD+RW 8x
20. DVD+R DL burning  Verbatim (MKM003) DVD+R DL 8x
21. DVDRAM burning  Maxell DVDRAM 5x, 12x
22. BDR burning  Panasonic BDR SL 6x (MEI RA1)
23. BDR burning  Sony BDR SL 6x (SONY NN3)
24. BDR burning  Verbatim BDR SL 6x LTH (VERBATIMu)
25. BDR Burning  Moser Baer BDR SL 6x (MBI R06)
26. BDR burning  Verbatim BDR SL 6x (VERBATIMe)
27. BDR burning Verbatim BDR SL 7.5GB 2x (VERBATIMa)
28. BDR DL burning  Panasonic BDR DL 6X (MEI RB1)
29. BDR DL burning  Verbatim BDR DL 6X (VERBATIMf)
30. BDR DL burning  TDK BDR DL 4x (TDKBLDRFB)
31. BDR DL burning  Verbatim BDR DL 2x (VERBATIMb)
32. BDRE burning  Verbatim BDRE SL 2X (VERBATIM0)
33. BDRE DL burning  BDRE DL 2x (VERBATIM1)
34. BDRE DL burning TDK BDRE DL 2X (TDKBLDWfa)
35. Summary of DVD, BD quality tests, Overburning, Booktype
36. Final words