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| JL Audio - 1200/1
v3
Owner’s Manual
11
select the filter frequency with a higher level
of precision, consult Appendix C: Chart A-4
(page 17) of this manual. The “Boost” control
determines how much boost (in dB) you are
adding to the bass signal. A range of 0 - 15dB
of boost is available. The “Remote Bass Port”
allows the connection of an optional remote
boost knob (the RBC-1) that can be mounted
in the front of the vehicle. This optional control
takes the place of the “Boost” knob on the
amplifier when connected and bypasses the
“Boost” control on the amplifier.
I M P O R TA N T
!
The “Advanced Bass Control” section will only
operate when the amplifier’s filter is activated
with the “Amp LP Filter” switch in the “12dB”
or “24dB” position. It will not work with this
switch in the “Off” position. This is to prevent
cascading the processing of multiple amplifiers
when configured in a master/Slave arrangement
as shown in Appendix D (page 18). If you are
using an external active crossover and would
like to use the “Advanced Bass Control”
features, set the “Amp LP Filter” switch on
“12dB” and rotate the frequency selection knob
fully clockwise to the “200 Hz” position. This
will activate the “LF Boost” and “Infrasonic
Filter” controls without significantly affecting
the crossover point selected by the external
active crossover.
subwooFer outPut
The 1200/1v3 employs JL Audio’s exclusive
Regulated, Intelligent Power Supply (R.I.P.S.)
design. This sophisticated power supply
allows the amplifier to produce its optimum
power (1200 watts x 1) over a wide range of
speaker impedances.
+12VDC
Ground
Remote
Low/High
Unlike conventional amplifiers that require
a specific impedance to produce optimum
power, the R.I.P.S.-equipped 1200/1v3 gives
you the freedom to use a variety of subwoofer
configurations that achieve final nominal
impedances between
1.5 – 4Ω (without sacrificing power output or
sound quality).
The operation of the R.I.P.S. circuitry is
entirely automatic and adjusts itself every time
the amplifier is turned on according to the lowest
impedance present at the speaker load. There are
no user controls to configure. The system
operates through multiple stages of impedance
optimization, choosing the stage most appropriate
to the actual impedance of the speaker(s) you
connect to it.
I M P O R TA N T
!
If you connect a load higher than 4Ω nominal
to the 1200/1v3, power will drop by half with
every doubling of impedance above 4Ω. If you
connect a load lower than 1.5Ω nominal to the
1200/1v3, the amplifier protection circuitry
activates a “safe” mode which reduces amplifier
power to protect the circuitry from failure (the
yellow LED on the top of the amplifier will
light to indicate that this has happened). See
page 12 for details.
3) “Out Filter”: The preamp output is filtered by a
fully variable, active filter incorporated into the
output section and is not affected by the bass
control processing selected for the amplifier.
In “Out Filter” mode, the user can select:
a) High-pass (“HP”) or low-pass (“LP”)
filtering by way of the “Filter Mode” switch.
b) 12 dB/octave or 24 dB/ octave filter slope by
way of the “Filter Slope” switch.
c) A filter cutoff frequency between 40 - 200
Hz for the preamp output signal by way of
the “Filter Control” switch.
This is completely independent of the
amplifier’s internal filter and allows the user to
match, stagger or overlap the subwoofer low-pass
filter frequency of the amplifier crossover with
the output filter’s frequency for precise control
and optimized midbass performance.
If you would like to select the filter frequency
with a higher level of precision, consult
Appendix C: Chart A-2 (page 16) of this manual.
C AU T I O N
!!
The signal level of the “Preamp Output” is
always low level regardless of the voltage
applied to this amplifier’s inputs and the
setting chosen on this amplifier’s “Input
Range” switch. All “Slave” amplifiers should
have their switches set to “Low”. See Appendix
D (page 18) for details.
adVanCed bass Control seCtion
The 1200/1v3 includes a versatile bass
processing section consisting of two
primary components: a fully variable,
24 dB per octave infrasonic filter and a
parametric, single-band equalizer.
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Low/High
1) “Infrasonic Filter”: The infrasonic filter is a
24 dB/octave high-pass filter, with a fully
variable cutoff frequency between 15 - 60 Hz.
When set at frequencies lower than 30 Hz, it
conserves amplifier power without audibly
affecting the quality of the sub-bass output. If
set at frequencies higher that 30 Hz, there will
be an audible effect, but one which may be
desirable for SPL competition purposes or curve
shaping of a bottom-heavy system. With ported
enclosures, the use of the infrasonic filter is
highly recommended to protect the speaker(s)
from excessive excursion below box tuning.
With sealed enclosures, the use of the filter is
less necessary, but can still help protect the
speaker system. If you would like to select the
infrasonic filter frequency with a higher level of
precision, consult Appendix C: Chart A-3 (page
17) of this manual. The infrasonic filter can be
completely defeated by selecting the “Off”
position on the “Mode” switch. This bypasses
all signal from flowing through the circuit.
2) Parametric Bass Equalizer: The parametric
equalizer allows the user to select the center
frequency of the boost band as well as the
bandwidth (“Q”) of the boost band. The “Q”
control selects the bandwidth of the boost
around the center frequency. Lower numbers
pertain to wider bandwidths while higher
number pertain to narrower bandwidths.
The “Center Freq.” control selects the center
frequency of the boost bandwidth within
a range of 20 - 80 Hz. If you would like to
