The Hitachi Hi-Saturn is not just another branded Saturn unlike the Victor (JVC) V-Saturn.  This Hitachi model come complete with the Video CD card and karaoke unit and even has a fully new opening sequence.  Hitachi were selling it as an all round Entertainment system that you could play games on, listen to music, watch your Video CDs and do a bit of karaoke.  I'm not too sure just how many of these where made or how well they sold.  It's certainly far more rare than the Victor V-Saturn.  The box that you can see under the Hi-Saturn is the karaoke interface.  This connects to the Hi-Saturn round the back as shown below.

The unit connects to the Saturn via a 2-way mini din plug that goes from the Saturn AV out in to the karaoke box. The power is fed from the Saturn through the AV connecting cable. The picture reaches the TV via the AV out on the karaoke box.

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