Sony KP-51WS500 Mode D'emploi page 226

Using the Menus
52
Option Description
Speaker ON
OFF
Audio Out Variable
Easy control
of volume
adjustments
Fixed
Select to turn on the projection TV speakers.
Select to turn off the projection TV speakers and
listen to the projection TV's sound only through
your external audio system speakers.
The projection TV's speakers are turned off, but
the volume output from your audio system can still
be controlled by the projection TV's remote
control.
The projection TV's speakers are turned off and the
volume, bass and treble output of the projection TV
is fixed. Use your audio receiver's volume control
to adjust the volume through your audio system.