JBL BP1200.1 Stereo Amplifier User Manual


 
5
Setting Input Level
Initially, turn the input-sensitivity LEVEL
control to its maximum (counter-clock-
wise) position. Turn on the source unit
and increase the volume control until it
is approximately three-quarters of maxi-
mum-output level. Slowly increase the
input LEVEL control (clockwise) while lis-
tening to the quality of the reproduced
sound. When you hear distortion on the
music peaks, turn the LEVEL control
back slightly. This is the maximum
undistorted output level of your system.
Turning the LEVEL control up farther
WILL NOT INCREASE THE OUTPUT
POWER OF YOUR AMPLIFIER! It will
only decrease the amount of volume-
control rotation before the amp is at full-
output power. It will also increase the
amount of extraneous noise present in
your system.
Wiring the Input-Signal
Connections
Connect a pair of signal cables with
RCA-type ends between the connectors
on the amplifier and the RCA-type signal
connectors on the source unit. If your
radio has only speaker-level outputs, you
should connect them to the speaker-level
input connectors, observing proper
polarity. When using the speaker-level
inputs, it is not necessary to connect a
wire between the “remote” terminal of
the amplifier and the “remote” lead from
the source unit. The speaker-level inputs
will sense voltage on the speaker
outputs and turn the amplifier on
automatically.
If you are installing a P80.4 amplifier and
your source unit has only one pair of
RCA-type output connectors and a pair
of speaker-level outputs, you may
connect the RCA outputs to a pair of
amplifier input channels (front or rear),
and the speaker-level outputs to the
other pair of amplifier input channels.
System Setup and Adjustment
Refer to figures 1–6 for location of
adjustment switches and controls.
Electronic Crossover and Bass Boost
P80.1, P80.4, P180.2
The electronic crossover can be selected
as a 12dB/oct. high-pass filter (HPF)
12dB/oct. low-pass filter (LPF) or it
can be defeated (FLAT). The crossover
frequency can be set at any frequency
between 32Hz and 320Hz.
BP150.1, BP300.1, BP600.1, BP1200.1
These amplifiers are designed to
drive subwoofers. Consequently, the
electronic crossover is a 12dB/oct.
low-pass filter which can be set at any
frequency between 32Hz and 320Hz.
The bass boost control will provide up
to 6dB of boost at 50Hz.
The BP150.1, BP300.1, BP600.1 and
BP1200.1 are designed to provide con-
stant bass regardless of the position of
the source unit’s front-to-rear fader posi-
tion. Use of this feature requires that all
four inputs are connected to the source
unit as labeled on the amplifier (front,
rear, right and left). If your source unit
has only one pair of RCA-type output
connectors and a pair of speaker-level
outputs, you may connect the RCA out-
puts to a pair of amplifier input channels
(front or rear), and the speaker level out-
puts to the other pair of amplifier input
channels. If nonfading bass is not impor-
tant in your system, connect a pair of
inputs, either speaker-level or RCA-type,
to either the front or rear input connec-
tors on the amplifier.
Power Series OM 4/15/99 9:17 AM Page 5