JBL PA454 User Manual page 13

The PA1254 lets you select either no filter (OFF) for a full-range
signal, or a high-pass filter (HPF) for your front channels if you're
powering a subwoofer with the rear channels. Slide the switch to
choose your desired crossover point.
For the rear channels, you can select between no filter (OFF); a
high-pass filter (HPF) if you're powering a subwoofer independently,
or a low-pass filter (LPF) if you're using the rear channels to power a
subwoofer in bridged mode. Slide the REAR – HZ switch to choose
your desired crossover point.
FRONT – HPF
OFF 60 80 120
The PA1502 lets you slide the X-OVER switch to select no filter (OFF)
for a full-range signal; a high-pass filter (HPF) if you're powering
speakers and have an independently powered subwoofer in your
system; or a low-pass filter (LPF) if you're powering a subwoofer
in bridged mode. Slide the FREQ. switch to choose your desired
crossover point.
X- OVER
OFF
The PA1502 also includes a bass boost (BOOST) switch for a +6dB
or +12dB boost at 45 Hz.
JBL APEX
REAR – Hz
60 80
HPF LPF 60
BOOST 45Hz – dB
+0 +6
REAR X- OVER
120 OFF
FREQ. – Hz
80 120
+12
HPF LPF
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