Subaru 1998 Impreza Owner's Manual page 136

Select the Treble control mode by pressing the "T/B" button. In the
treble control mode, the display shows the indication as shown.
The treble control has total of 13 volume levels (TR: –6 for minimum, 0
for middle, TR: +6 for maximum). Choose desired treble volume level
by turning the volume control knob. The control function returns to vol-
ume control mode after about 5 seconds.
B Fader control
Fader control indication
Select the Fader control mode by pressing the "T/B" button. In the
fader control mode, the display shows the indication as shown.
The fader control has total of 25 settings (F: 12 for front maximum and
rear minimum, 0 for neutral, R: 12 for front minimum and rear maxi-
mum). Choose desired setting by turning the volume control knob.
The control function returns to volume control mode after about 5 se-
conds.
5-6
When the fader setting is at the F12
(front maximum and rear minimum)
HG0089 HG0090