The most interesting feature of the new Pioneer BDXL burner is its support for BDXL discs. The BDXL specification was initially targeted primarily at commercial segments such as broadcasting, medical and document imaging enterprises with significant archiving needs. However, many consumer Blu-ray disc players have been supporting the format, especially those appearing at the Japanese market. The BDXL discs will be available in write-once versions with capacities of 100GB (BD-R TL) and 128GB (BD-R QL) and also in 100GB rewritable versions (BD-RE TL). The discs reach these capacities by incorporating three to four recordable layers.

Currently, only TDK / Imation makes BD XL recordable discs. These discs feature three recordable layers and are able to hold up to 100GB of data (95.6 GB to be exact). TDK's BD-R TL (Triple Layer) discs carry the TDKBLDRNC (MID. Here is some information on these discs, as it is reported by OptiDrive Control utility:

Currently, Sony, Sharp and Panasonic are also using TDK's discs in an OEM basis and offer them under their brands. Mitsubishi Kangaku Media (MKM), the company better known for its Verbatim brand, will also release its own BD-R TL (100GB) discs sometime later this year.

Pioneer's drive is supposed to support BD-R QL and BD-RE TL discs. However, BD-R QL are not yet available at the market (will they ever be?) and only Panasonic has released BD-RE TL discs for 2x recording in Japan (MID "PAN___EC2").

The BDXL discs require hardware (players/recorder) that is compatible with the BDXL format and carry the corresponding logo. So previous generation BD players or recorders/burners cannot recognize the discs.

The BDXL format is specified in six format books for both recordable and rewritable discs:

This version was defined in June 2010 and is a multi-layered recordable in BDAV with the speed of 2X and 4X, capable of 100/128GB and usage of UDF2.5/2.6 as file system:

• System Description Blu-ray Disc Recordable Part 1: Basic Format Specifications Ver. 2.0 June, 2010
• System Description Blu-ray Disc Recordable Part 2: File System Specifications Ver. 2.0 June, 2010
• System Description Blu-ray Disc Rewritable Part 3: Audio Visual Basic Specifications Ver.4.01 Sept. 2010 together with System Description Blu-ray Disc Rewritable Format Part 3: Audio Visual Basic Specifications Ver.2.13 Sept. 2010

This version was defined in June 2010 and is a multi-layered rewritable in BDAV with the speed of 2X and 4X, capable of 100GB and usage of UDF2.5 as file system.

• System Description Blu-ray Disc Rewritable Part 1: Basic Format Specifications Ver.3.0 June, 2010
• System Description Blu-ray Disc Rewritable Part 2: File System Specifications Ver.3.0 June, 2010
  
• System Description Blu-ray Disc Rewritable Part 3: Audio Visual Basic Specifications Ver.4.01 Sept. 2010 together with System Description Blu-ray Disc Rewritable Format Part 3: Audio Visual Basic Specifications Ver.2.13 Sept. 2010

Compared to the BD-R DL, the BD-R TL disc features three layers of data (L0, L1 and L2), with a thickness of 100um(L0),75um(L1) and 57um(L2). The thickness of the L0 and the L1 are the same for both BD-R DL, the BD-R TL. However, each layer of the BD-R TL disc holds 33.4GB of data, which is 8.4GB more than what the layers of BD-R SL and DL can hold (25GB). In order to achieve this, the BD-R TL features an increased linear density. It uses shorter marks on the recording layer (112nm for BD-R TL) and also applies the Integrated-Maximum-Likelihood-Sequence-Error-Estimation technology or i-MLSE using PR(1,2,2,2,1) signal quality evaluation index. Other than that, the BDXL discs use the same addressing and modulation method also met with legacy BD-R SL and DL media.

So the main difference with legacy BD-R format are cover layer thickness distribution, capacity per layer, minimum mark length and evaluation index for signal quality. For both TL and QL, the BDA has specified 2X and 4X recording of 72~144Mbps user transfer rate.

The following table shows the main parameters of BD-R, including for both TL of 100GB capacity and QL of
128GB capacity format:

In BDXL, the Inter-Symbol-Interference (ISI) of the readout signal becomes much stronger compared to the prior format that allows just 25GB per layer. Therefore the readout signal processing needs to be improved. Also, the prior signal quality evaluation method using the Limit-Equalizer technology has turned out to be no longer applicable. The Integrated-Maximum-Likelihood –Sequence-Error-Estimation (i-MLSE), which is an alternative signal quality evaluation method for BDXL, was newly developed by Sony and Panasonic and was first presented two years ago. The i-MLSE retains the stability and the precision in such a severe ISI condition of BDXL. The evaluation method of i-MLSE stands on the detection principle of the Viterbi-Algorithm (VA) in the Partial-Response-Maximum-Likelihood (PRML) readout signal processing.

Additionally, some contrivances can be incorporated to achieve the better correlation with the Symbol-Error-Rate (SER). For example, the tendency of error occurrences with the PR(1,2,2,2,1) ML readout in the BDXL is considered. Another feature of i-MLSE is that the mathematical expression is the same as that of Time-Interval-Jitter (TI-Jitter or Jitter, simply), which is the prior signal quality evaluation method.

Consequently, the behavior of i-MLSE is very similar to that of the TI-Jitter. This helps people who evaluate the BDXL discs or systems for the first time to comprehend the meaning of measured values obtained through i-MLSE because the TI-Jitter has been used so long since the era of CDs and is very familiar to them.

Burning a TDK BD-R TL disc

For our burning tests, we used the Pioneer BDR-2207 (BD-R 207M) v1.21 burner and a TDK BD-R TL disc (TDKBLDRNC (000)). The drive supports 6X burning and 4X reading for the specific disc. That's 2X higher than the company's previous generation BDXL drive, the Pioneer BDR-206M.

For the test we created a Blu-ray UDF compilation using Cyberlink's Power2Go software, which is bundled with the drive.

Prior to burning, the Cyberlink's software showed that the disc can hold 95.442 GB of data

The procedure is very simple, just drag'n'drop the files you want to burn to the disc to the right side of the software' s window.

Our compilation included multiple data files (95.463 GB):

Below you see information about the drive, the empty BDR XL disc and the data compilation we are about to burn:

We selected the UDF 2.5 file system for this burn:

The Pioneer drive supports the 2x, 4x and 6x for burning on the TDK disc. We also chose to finalize the disc finalization. You'd better also enable the disc verification option when you burn data in order ensure your files will be correctly burned on the disc.

The actual burning process did not start immediately, as the software had to prepare the compilation first. This took almost 9 minutes for the software to prepare the huge burning compilation before actually start burning the disc:

The writing process is in full progress:

Burning finished after 1hr 35 minutes and 11 seconds. That's not so fast as we expected, as Pioneer's previous generation BDXL drive, the BDR-206M was just 10 minutes slower for the same task at 4X.

Of course, the actual burning time is almost 1hr and 27 minutes, without the time the software did to "prepare" the data before starting burning the disc.

The files on the TDK BD-R TL disc were readable and easily accessible the readable through Windows Explorer. Below you see some more tests with the recorded TDK BDRTL disc loaded to the drive: