BASSPRO II (serv.man10) - JBL Car Audio Service Manual (repair manual). Page 6

BassPro II has controls and indicators
that help simplify sonic integration with
almost any vehicle’s unique acoustic
properties. These controls are located
on the amplifier panel, as shown in
Figure 10.

Power LED
Gain Control
Crossover
Remote Bass Control
Auto Turn-On 

POWER LED: This indicator 
will glow red when the BassPro II 
is operating.

GAIN CONTROL: Use this 
control to adjust the relative volume
(loudness) of BassPro II with the other
speakers in the vehicle.

CROSSOVER: Use this control 
to adjust the amount of high-frequency
information present in BassPro II’s out-
put. A lower value signifies less high-
frequency content.

3. Turn the head unit ON and play a

selection of your favorite music
track that has substantial bass. 

4. Adjust the CROSSOVER control

counterclockwise, until you hear
only low-frequency information. 
Example – you should not hear
vocals coming from BassPro II 
when seated in the normal listening 
position.

5. Adjust the BASS CONTROL either

clockwise or counterclockwise to
suit your taste, and to avoid audible
distortion.

6. If you elect not to install the Remote

Bass Control, adjust the GAIN 
control to the maximum level that
provides undistorted output from 
the BassPro II, with the head unit’s
volume control at its 3 o’clock 
setting.

NOTE: In most cases the above steps
will provide you with satisfactory
results. However, the actual process
may require several readjustments of
each control, since the settings will
interact with one another. If necessary,
consult your authorized JBL car audio
dealer for help in tuning your system.

AUTO TURN-ON: For speaker-
level connections, used this switch to
activate (or deactivate) BassPro II’s
automatic turn-on circuit. For most
speaker-level applications, slide the
switch to the AUTO position. If you 
prefer to use the remote (REM) 
connection, slide the switch to the 
OFF position.

REMOTE BASS
CONTROL: Use this RJ-11 jack 
to connect the supplied remote bass
control.

SETTING THE CONTROLS:
1. Make sure the head unit is off and

VOLUME control is set to minimum.

2. On BassPro II’s amplifier panel, set

the CROSSOVER to its maximum 
frequency of 120Hz, as shown in
Figure 10. 

NOTE: If using the REMOTE BASS
CONTROL, set GAIN to maximum 
and set the BASS CONTROL to the 
midpoint.

 BassPro II

         

 

 

 

   

 

 

 

   

 

 

       

 

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