6
O P E R A T I O N
When the unit is plugged in
and the power switch is on
and no signal is received, the
LEDs on the front of the unit
will turn red. When a signal is
present, the LEDs will turn
green.
Note: It will take several
minutes for the LEDs to turn
from green to red after the
input signal to the subwoofer
is removed. Due to JBL’s
unique, high-output, high-
efficiency amplifier design,
power consumption is minimal
when the subwoofer is not
receiving a signal. Of course,
the subwoofer can be turned
off, whenever desired.
The subwoofer Level Control
adjusts the volume of the
subwoofer relative to the rest
of the system. Proper level
adjustment depends on
several variables such as
room size, subwoofer
placement, type of main
speakers and listener position.
Adjust the subwoofer level so
that the volume of the bass
information is pleasing to you.
Crossover Adjustments
The Crossover Frequency
Control determines the highest
frequency at which the
subwoofer reproduces sounds.
If your main speakers can
comfortably reproduce some
low-frequency sounds, set this
control to a lower frequency
setting, between 50Hz – 100Hz.
This will concentrate the
subwoofer’s efforts on the
ultradeep bass sounds
required by today’s films and
music. If you are using smaller
bookshelf speakers that do not
extend to the lower bass
frequencies, set the low-pass
crossover control to a higher
setting, between 120Hz –
150Hz. This control is not used
when the LFE switch is in the
“LFE” position.
CROSSOVER
FREQUENCY
LEVEL
LINE LEVEL IN
PHASE
Min
Max
L
R
L R
For LFE use L or R
LFE NORMAL
PowerBass PB10
PowerBass PB10
HIGH
LEVEL
IN
L
R
POWER
HIGH
LEVEL
OUT
+ –
120V
60Hz
50Hz
0º
180º
150Hz
PowerBass PB12
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
120V
60Hz
CROSSOVER
FREQUENCY
LEVEL
LINE LEVEL IN
PHASE
Min
Max
L
R
L R
For LFE use L or R
LFE NORMAL
PowerBass PB12
HIGH
LEVEL
IN
L
R
HIGH
LEVEL
OUT
+ –
50Hz
0º
180º
150Hz
ON
OFF
POWER
ON
OFF
Level Control
Power