8
| JL Audio - 600/1
v3
Owner’s Manual
9
CrossoVer Controls
Crossovers are groups of individual electronic
filters which allow only certain frequency
ranges to pass through them by attenuating
frequencies outside the selected range. These
filters allow the user to specify what frequency
range will be sent out of each channel section
of the amplifier. This, in turn, allows each
speaker system to only reproduce a range of
frequencies it is well-suited for, resulting in
reduced distortion and improved fidelity.
amPliFier low-Pass Filter
The 600/1v3 employs a sophisticated, state-
variable, low-pass active filter for its internal
channel. This feature is designed to attenuate
frequencies above its filter frequency, so that the
system’s subwoofers do not reproduce any audible
midrange content.
+12VDC
Ground Remote
Preamp Output Section
Infrasonic Filter
“Q”
Center Freq.
Boost (dB)
Amp LP Filter
Advanced
Bass
Control
Amplifier Input Section
Subwoofer Output
MONO OUTPUT ONLY
Left Output
Right Output
Left Ch.
Right Ch.
Filter Freq. (Hz)
Filter Freq. (Hz)
Infrasonic Freq. (Hz)
Remote Bass Port
Full Range | Amp Filter | Out Filter
Output Mode
Filter Slope
Mode
Mode | Slope
Input Voltage
Input Sens. Signal Sensing
12dB | 24dB
Filter Mode
LP | HP
Bass EQ
Off | On
Off | 12dB | 24dB
Low | High
Off | On
Off | On
40
45
55
65
80
100
200
15
18
22
30
45
55
60
40
45
55
65
80
100
200
0.5
0.7
1.1
1.6
2.7
4.3 20
25
30
40
60
75
80
0
+4
+10
+13
+15
Monoblock Subwoofer Amplifier
1) Filter Operation: The low-pass filter in the
600/1v3 is fully variable between 40 Hz and
200 Hz via the “Filter Freq.” control knob
and features the ability to select between a
moderate “12dB” per octave or a steep “24dB”
per octave slope via the “Mode/Slope” switch.
Depending on the subwoofer system and the
vehicle, different slopes may be required to
produce a smooth transition to the mid-bass
speakers in the system. Experiment to find
the slope which best matches the acoustic
requirements of your system.
Tuning Hint
:
A trunk mounted sub whose output
has to "fight" through a rear deck or a back seat
often benefits from the 12 dB/octave slope which
lets more upper bass content pass through. A sub
that fires directly into the listening environment
is more likely to benefit from a 24 dB/octave slope.
The above hint is not “set-in-stone”…
You should always listen to the system carefully to
determine the best choice as vehicle acoustics and
other factors play a big role in choosing the most
appropriate filter slope.
ranges, accessible via switches located in the
“Amplifier Input Section” of the amplifier.
The “Low” position on the “Input Voltage”
switch selects an input sensitivity range
between 200mV and 2V. This means that
the “Input Sens.” rotary control will operate
within that voltage window. If you are using
an aftermarket source unit, with conventional
preamp-level outputs, this is most likely the
position that you will use. The “High” position
on the “Input Voltage” switch selects an input
sensitivity range between 800mV and 8V. This
is useful for certain high-output preamp level
signals as well as speaker-level output from
source units and small amplifiers. To use
speaker-level sources, splice the speaker output
wires of the source unit or small amplifier
onto a pair of RCA cables or plugs or use the
JL Audio ECS Speaker Wire to RCA adaptor
(XD-CLRAIC2-SW).
I M P O R TA N T
!
The output of the amplifier will decrease
for a given input voltage when the “Input
Range” switch is placed in the “High” position.
Conversely, the output will be higher with
the switch in the “Low” position. While this
may sound counter-intuitive, it is correct
as described.
3) Input Sensitivity Adjustment: Located
next to the “Input Voltage” switch, in the
“Amplifier Input Section”, is a rotary control
labeled “Input Sens.”. Once the appropriate
“Input Voltage” range has been selected, this
rotary control can be used to match the source
unit’s output voltage to the input stage of the
amplifier for maximum clean output. Rotating
the control clockwise will result in higher
sensitivity (louder for a given input voltage).
Rotating the control counter-clockwise will
result in lower sensitivity (quieter for a given
input voltage). To properly set the amplifier
for maximum clean output, please refer to
Appendix A (page 14) in this manual. After
using this procedure, you can then adjust
the level of the amplifier by adjusting the
input sensitivity downward, if the amplifier
requires attenuation to achieve the desired
system balance. Do not increase the “Input
Sens.” setting for any amplifier in the system
beyond the maximum level established during
the procedure outlined in Appendix A (page
14). Doing so will result in audible distortion
and possible speaker damage.
