FORD 2002 F-550 v.1 - Manual (Page 27)

If the volume is set above a certain level and the ignition is turned off,
the volume will come back on at a “nominal” listening level when the
ignition switch is turned back on.
Bass adjust
The bass adjust control allows you
to increase or decrease the audio
system’s bass output.
Treble adjust
The treble adjust control allows you
to increase or decrease the audio
system’s treble output.
Speaker balance adjust
Speaker sound distribution can be
adjusted between the right and left
speakers.
BASS
TREB
BAL
Entertainment systems
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