Ford E150 2002 Owner's Manual page 23

Entertainment Systems
Bass adjust
The bass adjust control allows you
to increase or decrease the audio
system's bass output.
BASS
Treble adjust
The treble adjust control allows you
to increase or decrease the audio
system's treble output.
TREB
Speaker balance adjust
Speaker sound distribution can be
adjusted between the right and left
speakers.
BAL
Speaker fade adjust
Speaker sound can be adjusted
between the front and rear
speakers.
FADE
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