After doing some google searches - this is what I found in a Marantz dv7600 manual:
"Image data values in RGB-Normal format range
between 16 (black) and 235 (white).
Image data values in RGB-Expand format range
between 0 (black) and 246 (white).
The formats available for HDMI outputs depend
on the connected TV or projector. For details,
see the users manual of your TV or projector.
Only RGB-Normal and RGB-Expand can be
selected for DVI outputs.
When black rise to the surface depending on
the display, black Setup in the Video Adjustment
set to OIRE.
YCbCr-1 (4:4:4) sends 8 bit data. YCbCr-2
(4:2:2) sends 10 bit data. If your TV or
projector supports YCbCr-2 (4:2:2), you can
enjoy the superior image quality of full 10 bit