Pontiac 2004 Grand Prix Owner's Manual page 221

Setting the Tone (Bass/Treble)
AUDIO: Push the AUDIO knob until BASS, MID, or
TREB appears on the display. Turn the knob to increase
or to decrease. If a station is weak or noisy, you may
want to decrease the treble.
To adjust bass, midrange, or treble to the middle position,
select BASS, MID, or TREB and push and hold the
AUDIO knob. The radio will produce one beep and adjust
the display level to zero.
To adjust all tone and speaker controls to the middle
position, push and hold the AUDIO knob when no tone or
speaker control is displayed. The radio will produce one
beep and CENTERED will appear on the display.
AUTO EQ (Automatic Equalization): Press this button
to choose between bass, midrange, and treble
equalization settings designed for country, jazz, talk,
pop, rock, and classical program types.
To return to the manual mode (CUSTOM), press the
AUTO EQ button until CUSTOM appears on the display.
Then you will be able to manually adjust the bass,
midrange, and treble using the AUDIO knob.
Adjusting the Speakers (Balance/Fade)
AUDIO: To adjust the balance between the right
and the left speakers, push the AUDIO knob until BAL
appears on the display. Turn the knob to move the
sound toward the left or the right speakers.
To adjust the fade between the front and rear speakers,
push and hold the AUDIO knob until FAD appears on
the display. Turn the knob to move the sound toward the
front or the rear speakers.
To adjust the balance and the fade to the middle
position, select balance or fade and push and hold
the AUDIO knob. The radio will beep once and
will adjust the display level to the middle position.
To adjust all tone and speaker controls to the middle
position, push and hold the AUDIO knob when no tone
or speaker controls are displayed. The radio will
produce one beep and CENTERED will appear on
the display.
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