Sony BWU-100A

It may be early days for the technology, but it's still interesting to look at Sony's Blu-Ray drive under the microscope.

The BWU-100A is Sony’s first foray into Blu-ray EIDE devices. This is not the first Blu-ray unit for PCs however. That title belongs to Pioneer’s BDR-101A. The distinction between the units is that Sony’s entry supports BD-R, BD-RE, DVD and, unlike the Pioneer unit, CD burning.



The BWU-100A is not a wholly Sony manufactured product. It’s made up of a Nichia OPU (Optical Pickup Unit)/blue-laser diode, a Panasonic drive-train and a Panasonic MN103S98HBA CPU/controller.

The challenge in blue laser diode production is integrating CD, DVD and BD writing functionality into one diode and managing to keep it from overheating/becoming unstable during the writing process. Sony has achieved this, for the most part, with the BWU-100A.

BWU-100A on the bench
For our tests, we used ImgBurn v2.1.0.0 and 25GB BD-RE media. We also employed the assistance of DVDInfoPro v4.6.1.7 to graph the OPC, CRC, verification time and CPU usage out of ImgBurn.

Optimal Power Calibration/Pickup Calibration (OPC) is a process where the OPU dynamically adjusts heat, light and timing variables to achieve a consistent result in the write process. This is evident in graphs where spikes/dips/fluctuations are displayed.



The unit showed consistent write speed at 2x. The OPU employed some OPC techniques every 4GB (yellow line) that suggested calibration/cooling/power adjustment needed to be made.

The verification CPU utilisation was too high, averaging 18 percent CPU. This suggested the unit and the controllers had some problems reading data back efficiently.

To achieve consistent 2x throughput, we had to turn off verification-on-write hardware error correction in ImgBurn, which would otherwise default the BWU-100A to writing at 1x. This is similar to DVD-RAM, which uses hardware error correction to make sure data is written correctly (hence, when you write DVD-RAM at 5x, it’s really recording at 2.5x).

Image verification was consistent and proved that, on the CRC level at least, despite some write quality issues, the Sony BWU-100A can write error free BD-R/BD-RE volumes to certified media. Over internal EIDE and USB 2.0/FireWire, the Sony drive was able to burn a 25GB BD-RE disc in 46 minutes.

The shiny stuff
TDK’s Durabis2 certified 2x media was used for our testing. As with all optical disc-based technologies now days, these discs have their own unique MID to identify the disc type. The tables below show the MID codes of the samples that were used.

TDK's BD-R write once 2x 25GB media

TDK's BD-R rewriteable 2x 25GB media

DVD burning on the BWU-100A
The unit’s DVD writing performance was commendable, but not ideal when compared to a reference unit, such as the Pioneer DVR-A11XLA. Figures 5 and 6 show parity results of RITEKF1 and MCC02RG20 media. The media couldn’t be written at full speed by the unit, reverting to 8x and 6x respectively.

RITEKF1 write at 8x

MCC02RG20 write at 6x

The higher quality, slower written MID (MCC02RG20) produced less desirable write quality results. This suggests the firmware on the BWU-100A needs considerable refinement, before DVD writing could be considered optimal.

Verdicts are us
After testing both Blu-ray and DVD performance, here’s what we see as being the BWU-100A pros and cons. The good and the bad.

Pros of the BWU-100A
• Consistent write speed to BD-R/RE media with low resource usage.
• Capable of writing a wide range of media, DVD-RAM, DVD+R/-R/DL/CD-R, BD-R, BD-RE/DL.
• HDCP capable firmware for output to a HDCP compliant environment.
• Solid construction. One of the heaviest optical drives on the market.
• Basically inaudible. A very quiet transport mechanism.

Cons of the BWU-100A
• Poor media support/MID table for DVD media.
• EIDE interface – give it up already, let it go.
• Inability to match correct write strategies for common DVD MIDs.
• Some write quality issues with BD-R/BD-RE media prevent optimal extraction speeds, resulting in extremely slow read back performance.
• Currently, the unit doesn’t support parity or jitter analysis of its native media types – hopefully firmware will change this.
• 4GB write ‘pause’ effect.

Conclusion
It’s early days yet. For relevant market segments, the BWU-100A is currently the only serious choice. Pro level/media producers look no further. The unit represents a well-rounded purchase compared to Pioneer’s entry to the market, but falls short on write quality due to the immaturity of firmware and blue laser diode production techniques.

From the pure performance perspective, unless you need 50GB on an optical disc right now, we suggest waiting for LG’s GBW-H10N or Pioneer’s BDR-102A unit to proliferate the market, promising 4x BD-R/RE burning to 2x certified media and overall better resource handling on the EIDE bus.