Plextor ConvertX PX-M402U - Page 2

The Converter

It is very interesting to see how this device works. The PX-M402U is capable of encoding/decoding video and encoding/decoding audio. But let us take a closer look at the device's mainboard.

Opening the device's case will void the warranty, so we advise against it. Instead, use the photos in this review for a closer look under the hood.

For reference reasons, we unscrewed the case and took the following photos. Clicking on the image below will open a higher resolution image.

One of the main advantages of this device is that the processing modes and methods are stored on the host computer. This is a clever approach by Plextor, since users can upgrade the used algorithm the device uses (since it is stored on the computer), without requiring any upgrade on the device itself. A simple update program is all you need.

Looking at the mainboard a little closer, we can see that it consists of a series of chipsets used for encoding or decoding the video and audio streams. To be more precise, it consists of the following:

Philips SAA7115HL NTSC/PAL/SECAM Video Decoder

WIS Technologies GO7007SB Video Encoder

Cypress CY7C68013 USB 2.0 controller

AKM 5355VT Stereo Sigma Delta ADC

Micron 4MB SDRAM

The mainboard uses rather simple processes to encode video/audio. It uses 4MB SDRAM to handle temporarily stored data. It receives the video signal from the S-Video or Composite input and transfers it to the Philips SAA7115HL that decodes the signal, sending it to the WIS Video Encoder for conversion, according to the selected user settings. The WIS encoder is the first encoder that is DivX Certified.

Audio is passed via the audio connectors to the AKM Stereo analog/digital converter, that converts analog audio signals to digital audio signals that can be handled by the M402U. The WIS Video encoder synchronises the video streams with the audio streams and transfers the video/audio digital signals to the Cypress USB2.0 controler to be saved to the hard disk on the host PC. \