Lexus GS300 1998 Owner's Manual page 232

AIR CONDITIONING AND AUDIO
21G007
"Type A
Each time you push the "AUDIO CONTROL" knob, the
display changes as in the following. To adjust the tone and
balance, turn the knob.
BASS: Adjusts low–pitched tones.
MID: Adjusts mid–pitched tones.
TREB: Adjusts high–pitched tones.
FADE: Adjusts the sound balance between the front and rear
speakers.
BAL: Adjusts the sound balance between the right and left
speakers.
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