Denon DVD-9000 Operating Lnstructions page 63

With DVDs containing multiple angle signals, the angle can be switched during playback
During playback, press the ANGLE button.
@ The current angle number is displayed.
cursor buttons to select the desired angle.
e The display turns off when the ANGLE button is pressed.
Remote control unit
\
'L_
'..
\\
Remote control unit
@ The multiple angle function only works with discs on which multiple angles are recorded.
* "ANGLE" lights on the main unit's display when playing a section recorded in the multi-angle mode.
@ At scenes where multiple angles are recorded, the angle can be switched.