JL Audio Stereo Amplifier 450 4V2 User Manual

OWNER’S MANUAL  
four-channel system amplifier  
Thank you for purchasing a JL Audio amplifier for  
your automotive sound system.  
Your amplifier has been designed and manufactured to exacting  
standards in order to ensure years of musical enjoyment in your vehicle.  
For maximum performance and extended warranty  
coverage, we highly recommend that you have your new amplifier  
installed by an authorized JL Audio dealer. Your authorized  
dealer has the training, expertise and installation equipment to ensure  
optimum performance from this product. Should you  
decide to install the amplifier yourself, please take the time  
to read this manual thoroughly so as to familiarize yourself  
with its installation requirements and setup procedures.  
If you have any questions regarding the instructions in this  
manual or any aspect of your amplifier’s operation, please contact your  
authorized JL Audio dealer for assistance. If you need further assistance,  
please call the JL Audio Technical Support Department  
at (954) 443-1100 during business hours.  
 
PROTECT YOUR HEARING!  
INSTALLATION APPLICATIONS  
Cooling Efficiency Considerations:  
We value you as a long-term customer. For  
that reason, we urge you to practice restraint in  
the operation of this product so as not to damage  
your hearing and that of others in your vehicle.  
Studies have shown that continuous exposure to  
high sound pressure levels can lead to permanent  
(irreparable) hearing loss. This and all other  
high-power amplifiers are capable of producing  
such high sound pressure levels when connected  
to a speaker system. Please limit your continuous  
exposure to high volume levels.  
This amplifier is designed for operation in  
vehicles with 12V, negative-ground electrical  
systems. Use of this product in vehicles with  
positive ground and/or voltages other than 12V  
may result in damage to the product and will void  
the warranty.  
This product is not certified or approved for  
use in aircraft.  
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amplifier with the outputs of a second amplifier,  
including an identical one.  
Your JL Audio amplifier employs an  
If mounting the amplifier under a seat,  
make sure there is at least 1 inch (2.5 cm) of  
space above the amplifier’s outer shell to permit  
proper cooling.  
advanced type of heat management, called  
RealSink™. This feature takes advantage of  
convection and radiation effects to remove  
heat from the amplifier circuitry. For optimum  
cooling performance, the vertical heat sinks  
located at the back of the amplifier should be  
exposed to as large a volume of air as possible.  
Enclosing the amplifier in a small, poorly  
ventilated chamber can lead to excessive heat  
build-up and degraded performance. If an  
installation calls for an enclosure around the  
amplifier, we recommend that this enclosure  
be ventilated with the aid of a fan. In normal  
applications, fan-cooling is not necessary, but  
you still need to follow some basic guidelines:  
Safety Considerations:  
Your amplifier needs to be installed in a dry,  
well-ventilated environment and in a manner  
which does not interfere with your vehicle’s safety  
equipment (air bags, seat belt systems, ABS brake  
systems, etc.). You should also take the time to  
securely mount the amplifier using appropriate  
hardware so that it does not come loose in the  
event of a collision or a sudden jolt to the vehicle.  
While driving, operate your audio system in  
a manner that still allows you to hear necessary  
noises to operate your vehicle safely (horns,  
sirens, etc.).  
PLANNING YOUR INSTALLATION  
It is important that you take the time to read  
this manual and that you plan out your  
installation carefully. The following are some  
considerations that you must take into account  
when planning your installation.  
Stupid Mistakes to Avoid:  
SERIAL NUMBER  
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pointing up: Optimum  
In the event that your amplifier requires  
service or is ever stolen, you will need to  
have a record of the product’s serial number.  
Please take the time to enter that number in  
the space provided below. The serial number  
can be found on the bottom panel of the  
amplifier and on the amplifier packaging.  
to make sure that you will not be drilling  
through a gas tank, brake line, wiring harness or  
other vital vehicle system.  
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the vehicle. This is an extremely dangerous  
practice which can result in severe damage to  
your vehicle and person.  
tꢀ"NQMJGJFSꢀNPVOUFEꢀIPSJ[POUBMMZꢁꢀ  
right side up: Good  
tꢀ"NQMJGJFSꢀNPVOUFEꢀIPSJ[POUBMMZꢁꢀCVUꢀVQTJEFꢀ  
down: Fair (not recommended if there is  
less than 1 inch (2.5 cm) clearance above the  
amplifier heat sinks)  
tꢀ"NQMJGJFSꢀNPVOUFEꢀWFSUJDBMMZꢀXJUIꢀIFBUꢀTJOLꢀGJOTꢀ tꢀ1SPUFDUꢀBMMꢀTZTUFNꢀXJSFTꢀGSPNꢀTIBSQꢀNFUBMꢀ  
Serial Number:  
pointing laterally: Fair  
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pointing down: Poor (not recommended)  
edges and wear by carefully routing them,  
tying them down and using grommets and  
loom where appropriate.  
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compartment, under the vehicle, on the roof  
or in any other area that will expose the  
amplifier circuitry to the elements.  
CH 3&4  
HP Filter Slope  
Selection / Defeat  
(pg. 9)  
CH 3&4  
Input Sensitivity  
Control  
CH 1&2  
Chassis Ground  
Connector  
(pg. 6)  
Infrasonic Filter  
On/Off Switch  
(pg. 11)  
CH 1&2 Input  
Sensitivity Control  
(pg. 8)  
CH 1&2  
Input Voltage  
Range Selector  
(pg. 7)  
Filter Slope  
Selection / Defeat  
(pg. 8)  
(pg. 9)  
CH 1&2  
CH 3&4  
CH 3&4  
+12 V Power  
Connector  
(pg. 6)  
Remote Turn-On  
Connector  
(pg. 7)  
Preamp Output  
Signal Selector  
(pg. 10)  
CH 1&2  
Speaker Outputs  
(pg. 11)  
Bass EQ  
On/Off Switch  
(pg. 11)  
CH 3&4  
Speaker Outputs  
(pg. 11)  
Filter Frequency  
Range Selector  
(pg. 9)  
Input Voltage  
Range Selector  
(pg. 7)  
Filter Frequency  
Range Selector  
(pg. 9)  
+12VDC Ground Remote  
Preamp Output Section  
CH 1 & 2 Speaker Outputs  
CH 1 & 2 Bass Control  
CH 1 & 2 Filter Section  
CH 1 & 2 Input Section  
CH 3 & 4 Filter Section  
CH 3 & 4 Input Section  
CH 3 & 4 Speaker Outputs  
|
Signal From  
Bass EQ  
Infrasonic Filter  
Freq. Range Filter Mode Slope  
Input Voltage Input Sens.  
Freq. Range High-Pass Filter  
Input Voltage Input Sens.  
|
|
|
|
|
|
|
|
|
|
|
|
1 & 2 3 & 4 All  
Off On  
Off 30Hz  
x1 x10 Off 12dB 24dB  
Low High  
x1 x10 Off 12dB 24dB  
Low High  
95  
95  
Either  
feature  
Filter Type  
Input Mode  
Also sets  
low-pass  
cutoff for  
CH 1 & 2  
Bandpass  
Filter  
75  
60  
50  
Filter Freq. (Hz)  
130  
75  
60  
50  
HP Filter Freq. (Hz)  
130  
200  
500  
sums the  
CH 1&2 input  
signals to  
mono when  
activated.  
200  
450/4v2  
Left  
ꢃꢂꢉ  
Right  
ꢃꢂꢉ  
Left  
ꢁꢂ  
Right  
ꢁꢂ  
Four-Channel System Amplifier  
|
|
|
ꢃꢄꢂꢅꢆꢇꢈ  
500  
LP BP HP  
2ch 4ch  
ꢃꢄꢂꢅꢆꢇꢈ  
(if selected)  
1 & 2  
1 & 2  
and  
Remote  
Bass Port  
CH 1  
(Left)  
CH 2  
(Right)  
CH 3  
(Left)  
CH 4  
(Right)  
Inputs  
Only  
Left Output Right Output  
Bridged: 300W x 1 (3-8Ω)  
Bridged: 150W x 1 (3-8Ω)  
3 & 4  
Left and Right  
Preamp Output Jacks  
(pg. 10)  
Jack for  
Remote Bass  
Control Knob  
(pg. 11)  
Selects CH 1&2  
CH 1&2  
Selects  
Selects CH 3&4  
High-Pass Cutoff  
Frequency and Low-Pass  
Cutoff for CH 1&2 Bandpass  
Filter  
CH 3&4  
Left and Right  
Input Jacks  
(pg. 7)  
2ch / 4ch  
Input Mode  
(pg. 7)  
Left and Right  
Input Jacks  
(pg. 7)  
HP or LP Cutoff  
Frequency or HP Cutoff  
of Bandpass Filter  
(pg. 8)  
(pg. 10)  
2 | JL Audio - 450/4v2 Owner’s Manual  
3
 
PRODUCT DESCRIPTION  
TYPICAL INSTALLATION SEQUENCE  
The following represents the sequence for  
a typical amplifier installation, using an  
aftermarket source unit or OEM Interface  
processor (like the CleanSweep® CL441dsp).  
Additional steps and different procedures may  
be required in some applications. If you have  
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JL Audio dealer for assistance.  
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connection and secure the disconnected cable  
to prevent accidental re-connection during  
installation. This step is not optional!  
2) Run power wire (minimum 4 AWG)  
from the battery location to the amplifier  
mounting location, taking care to  
route it in such a way that it will not be  
damaged and will not interfere with  
vehicle operation. Use 2 AWG or 1/0  
AWG power wire if additional amplifiers  
are being installed with the 450/4v2.  
3) Connect power wire to the positive battery  
post. Fuse the wire with an appropriate fuse  
block (and connectors) within 18 inches (45  
cm) wire length of the positive battery post.  
This fuse is essential to protect the vehicle.  
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has been connected to the amplifier.  
The JL Audio 450/4v2 is a four-channel system  
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Class AB technology for all channels. All  
channels benefit from JL Audio’s exclusive R.I.P.S.  
QPXFSꢀTVQQMZꢀEFTJHOꢀXIJDIꢀPQUJNJ[FTꢀUIFꢀPVUQVUꢀ  
of each channel pair for any impedance between  
1.5 and 4 ohms per channel.  
The staggered power distribution of the 1&2  
and 3&4 channel pairs (150W x 2 for CH 1&2 and  
75 x 2 for CH 3&4) allows for a wide variety of  
application options. The 450/4v2 can be operated  
in the following modes:  
The 450/4v2’s flexible input and crossover  
sections permit operation with a wide variety  
of source units and system configurations. The  
450/4v2 can operate with a single pair of stereo  
inputs or with separate inputs for CH 1&2 and  
CH 3&4, if the source unit is equipped with front  
and rear outputs. The 450/4v2’s preamp output  
can send pass-through signals from the CH 1&2  
inputs only or the CH 3&4 inputs only or it can  
sum all four input channels to feed a subwoofer  
amplifier. This latter mode allows for non-fading  
sub-bass with front to rear satellite fading.  
As we said, it’s very flexible.  
7) Securely mount the amplifier using  
appropriate hardware.  
8) Connect the positive and negative power  
wires to the amplifier. A fuse near the  
amplifier is not necessary.  
9) Connect the remote turn-on wire  
to the amplifier.  
10) Connect the RCA input cables  
to the amplifier.  
11) Connect the speaker wires to the amplifier.  
12) Carefully review the amplifier’s control  
settings to make sure that they are set  
according to the needs of the system.  
13) Install power wire fuse (60A for a  
single 450/4v2) and reconnect the negative  
battery post terminal.  
14) Turn on the source unit at a low level  
to double-check that the amplifier is  
configured correctly. Resist the temptation  
to crank it up until you have verified the  
control settings.  
15) Make necessary adjustments to the input  
sensitivity controls to obtain the right  
overall output and the desired balance  
in the system. See Appendix B (page 22)  
for the recommended input sensitivity  
setting method.  
1) As a full-system amplifier in bi-amp mode with  
CH 1&2 driving subwoofers in low-pass mode  
(150W x 1 or 300W x 1) and CH 3&4 driving  
main speakers in high-pass mode (75W x 2).  
2) As a high power four-channel satellite  
amplifier in a bi-amplified system, delivering  
high-passed signals to front and rear speaker  
systems. In this mode, we recommend that CH  
1&2 drive the front speaker systems and CH  
3&4 drive the rear speaker systems. Preamp  
outputs permit connection of a separate  
amplifier to drive the subwoofer system.  
3) As a high power four-channel satellite  
amplifier in a tri-amplified system,  
delivering band-passed signals through  
CH 1&2 to mid-bass speakers and high-  
passed signals through CH 3&4 to mid-  
range/ tweeter speaker systems. Preamp  
outputs permit connection of a separate  
amplifier to drive the subwoofer system.  
4) As a high power three-channel satellite  
amplifier, delivering 150W x 3 at 4Ω in high-  
pass mode to left, center and right speaker  
systems. This requires bridging the outputs of  
CH 3&4 to create an equal power third channel  
to complement CH 1&2. Preamp outputs  
permit connection of a separate amplifier to  
drive the subwoofer system.  
4) Run signal cables (RCA cables) and remote  
turn-on wire from the source unit to the  
amplifier mounting location.  
5) Run speaker wire from the speaker systems to  
the amplifier mounting location.  
6) Find a good, solid metal grounding point  
close to the amplifier and connect the  
negative power wire to it using appropriate  
hardware. Use minimum 4 AWG power wire,  
no longer than 36 inches (90 cm) from the  
amplifier to the ground connection point. In  
some vehicles, it may be necessary to upgrade  
the battery ground wire. (See page 6 for  
important notice).  
16) Enjoy the fruits of your labor with your  
favorite music.  
4 | JL Audio - 450/4v2 Owner’s Manual  
5
 
POWER CONNECTIONS  
TURN-ON LEAD  
Before installing the amplifier,  
The ground connection should be made using  
the same gauge wire as the power connection  
(4 AWG) and should be kept as short as possible,  
while accessing a solid piece of sheet metal in the  
vehicle. The surface of the sheet metal should  
be sanded at the contact point to create a clean,  
metal-to-metal connection between the chassis  
and the termination of the ground wire. For  
optimal grounding, we recommend the use  
of a JL Audio ECS master ground lug  
(XB-MGLU). Alternatively, a sheet metal  
screw or bolt can be used with a star washer.  
Any wires run through metal barriers (such  
as firewalls), must be protected with a high  
quality insulating grommet to prevent damage  
to the insulation of the wire. Failure to do so  
may result in a dangerous short circuit.  
The 450/4v2 uses a conventional +12V remote  
turn-on lead, typically controlled by the source  
unit’s remote turn-on output. The amplifier will  
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input and turn off when +12V is switched off. If  
a source unit does not have a dedicated remote  
turn-on output, the amplifier’s turn-on lead can  
be connected to +12V via a switch that derives  
power from an ignition-switched circuit.  
5IFꢀꢆꢇꢈꢉꢆWꢅꢊTꢀiRemotewꢀUVSOꢋPOꢀDPOOFDUPSꢀ  
is designed to accept 18 AWG – 8 AWG wire. 12  
AWG is more than adequate for this purpose.  
To connect the remote turn-on wire to the  
amplifier, first back out the set screw on the top  
of the amplifier, using the supplied hex wrench.  
Strip 1/2 inch (12mm) of wire and insert the  
bare wire into the receptacle on the front panel  
of the amplifier, seating it firmly so that no bare  
wire is exposed. When using smaller wire, it may  
be necessary to strip 1 inch of insulation from  
the wire and fold the bare wire in half prior to  
insertion. While holding the wire in the terminal,  
tighten the set screw firmly, taking care not to  
strip the head of the screw and making sure that  
the wire is firmly gripped by the set screw.  
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BOꢀiInput ModewꢀTXJUDIꢀUPꢀBMMPXꢀPQFSBUJPOꢀPGꢀ  
all four amplifier channels with one or two pairs  
of input signals.  
disconnect the negative (ground) wire  
from the vehicle’s battery. This will prevent  
accidental damage to the system, the vehicle  
and your body during installation.  
1) Input Mode Switch: If you wish to operate all  
four channels of the 450/4v2 with a single pair  
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pair of input cables to the input jacks in the  
iCH 1&2 Input Sectionwꢌꢀꢀ*OꢀUIJTꢀNPEFꢁꢀUIFꢀ  
amplifier will route the signals connected to  
the CH 1&2 inputs to CH 3&4 as well.  
+12VDC Ground Remote  
450/4v2  
Four-Channel System Amplifier  
If you wish to use separate inputs for CH 1&2  
and CH 3&4 (to allow front-to-rear fading, for  
example) and the source unit is equipped with  
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ModewꢀTXJUDIꢀMPDBUFEꢀJOꢀUIFꢀiCH 1&2 Input  
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pairs of input cables to each input section.  
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connections are designed to accept 4 AWG power  
wire. 4 AWG is the only recommended power  
XJSFꢀTJ[FꢀGPSꢀUIJTꢀBNQMJGJFSꢌꢀ  
If you are installing the 450/4v2 with other  
amplifiers and wish to use a single main power  
wire, use 2 AWG or 1/0 AWG main power wire  
(depending on the overall current demands of  
all the amplifiers in the system). This 2 AWG  
or 1/0 AWG power wire should terminate into  
a distribution block mounted as close to the  
amplifiers as possible and should connect to the  
450/4v2 with 4 AWG power wire.  
IMPORTANT  
!
Many vehicles employ small (10 AWG - 6 AWG)  
wire to ground the battery to the vehicle chassis  
and to connect the alternator’s positive  
connection to the battery. To prevent voltage  
drops, these wires should be upgraded to 4  
AWG when installing amplifier systems with  
main fuse ratings above 60A.  
2) Input Voltage Range: A wide range of signal  
input voltages can be accommodated by each  
of the 450/4v2’s input sections (200mV – 8V).  
This wide range is split up into two sub-ranges,  
accessible via switches located in each input  
section of the amplifier. Be aware that each  
JOQVUꢀTFDUJPOꢊTꢀiInput VoltagewꢀTXJUDIꢀXJMMꢀ  
have to be configured, regardless of how many  
input cables are actually feeding the amplifier.  
5 I F ꢀi LowwꢀQPTJUJPOꢀPOꢀFBDIꢀiInput Voltagewꢀ  
switch selects an input sensitivity range  
between 200mV and 2V. This means that the  
iInput Sens.wꢀSPUBSZꢀDPOUSPMꢀXJMMꢀPQFSBUFꢀ  
within that voltage window. If you are using an  
aftermarket source unit, with conventional  
preamp-level outputs, this is most likely the  
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POꢀFBDIꢀiInput VoltagewꢀTXJUDIꢀTFMFDUTꢀBOꢀ  
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.  
CH 1&2 / CH 3&4 INPUT SECTIONS  
The 450/4v2 has two separate input sections,  
one for CH 1&2 and another for CH 3&4. Each  
section contains a pair of RCA-type input jacks,  
BOꢀiInput VoltagewꢀTXJUDIꢀBOEꢀBOꢀiInput Sens.wꢀ  
rotary control.  
Fuse Requirements  
Note: Smaller AWG numbers mean bigger wire  
and vice-versa (1/0 AWG is the largest,  
2 AWG is smaller, then 4 AWG, then  
8 AWG, etc.).  
It is absolutely vital that the main power  
wire(s) to the amplifier(s) in the system be  
fused within 18 inches (45 cm) of the positive  
battery post connection. The fuse value at each  
power wire should be high enough for all of the  
equipment being run from that power wire. If  
only the 450/4v2 is being run from that power  
wire, we recommend a 60A fuse be used. AGU  
(big glass fuse) or MaxiFuse™ (big plastic-body  
fuse) types are recommended.  
CH 1 & 2 Input Section  
CH 3 & 4 Input Section  
Input Voltage Input Sens.  
Input Voltage Input Sens.  
To connect the power wires to the amplifier,  
first back out the set screw on the top of the  
amplifier, using the supplied 2.5 mm hex wrench.  
Strip 1/2 inch (12 mm) of insulation from the  
end of each wire and insert the bare wire into  
the receptacle on the front panel of the amplifier,  
seating it firmly so that no bare wire is exposed.  
While holding the wire in place, tighten the set  
screw firmly, taking care not to strip the head  
of the screw.  
|
Low High  
|
Low High  
Input Mode  
|
2ch 4ch  
1 & 2  
1 & 2  
and  
CH 1  
(Left)  
CH 2  
(Right)  
CH 3  
(Left)  
CH 4  
(Right)  
Inputs  
Only  
No fuse is required or recommended directly  
before the amplifier power connection. If one is  
desired, we recommend the use of a 60A AGU  
fuse or MaxiFuse™ type.  
3 & 4  
To use speaker-level sources, splice the speaker  
output wires of the source unit or small  
amplifier onto a pair of RCA plugs for each  
input pair or use the JL Audio ECS Speaker  
Wire to RCA adaptor (XB-CLRAIC2-SW).  
6 | JL Audio - 450/4v2 Owner’s Manual  
7
 
IMPORTANT  
!
CROSSOVER CONTROLS  
CH 3&4 Filter Section:  
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.  
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.  
2) iFilter Mode/Slopewꢀ$POUSPMꢍꢀ5IJTꢀTXJUDIꢀ  
allows you to defeat the CH 1&2 filter or select  
from two filter slopes.  
CH 3 & 4 Filter Section  
CH 3  
Freq. Range High-Pass Filter  
Inpu  
|
|
|
x1 x10 Off 12dB 24dB  
Low  
95  
Mode  
Also sets  
130  
iOffwꢍꢀ%FGFBUTꢀUIFꢀGJMUFSꢀGPSꢀ$)ꢀꢂꢎꢅꢀDPNQMFUFMZꢁꢀ  
allowing the full range of frequencies present  
at the inputs to feed that pair of channels.  
5IJTꢀJTꢀVTFGVMꢀGPSꢀTZTUFNTꢀVUJMJ[JOHꢀPVUCPBSEꢀ  
crossovers or requiring full-range reproduction  
from that pair of channels.  
75  
60  
50  
HP Filter Freq. (Hz)  
low-pass  
cutoff for  
200  
500  
CH 1 & 2  
Bandpass  
Filter  
|
4ch  
(if selected)  
1 & 2  
and  
3 & 4  
(
3) Input Sensitivity Adjustment: Located next  
UPꢀUIFꢀiInput VoltagewꢀTXJUDIꢀJOꢀFBDIꢀJOQVUꢀ  
TFDUJPOꢀJTꢀBꢀSPUBSZꢀDPOUSPMꢀMBCFMFEꢀiInput  
Sens.wꢌꢀ0ODFꢀUIFꢀBQQSPQSJBUFꢀiInput Voltagewꢀ  
range has been selected, this control can be  
used to match the source unit’s output voltage  
to the input stage of each pair of amplifier  
channels 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 each pair  
1) i High-Pass Filterwꢀ$POUSPMꢍꢀ5IJTꢀTXJUDIꢀBMMPXTꢀ  
you to defeat the CH 3&4 filter or select from  
two different filter slopes.  
CH 1&2 Filter Section:  
i 12dBwꢍꢀ$POGJHVSFTꢀUIFꢀGJMUFSꢀGPSꢀ$)ꢀꢂꢎꢅꢀ  
to attenuate frequencies above or below the  
selected filter frequency at a rate of 12 dB per  
octave (Butterworth alignment).  
trol  
CH 1 & 2 Filter Section  
|
c Filter  
Freq. Range Filter Mode Slope  
Input V  
i Offwꢍꢀ%FGFBUTꢀUIFꢀGJMUFSꢀGPSꢀ$)ꢀꢏꢎꢆꢀDPNQMFUFMZꢁꢀ  
allowing the full range of frequencies present  
at the inputs to feed that pair of channels.  
5IJTꢀJTꢀVTFGVMꢀGPSꢀTZTUFNTꢀVUJMJ[JOHꢀPVUCPBSEꢀ  
crossovers or requiring full-range reproduction  
from these channels.  
|
|
|
|
0Hz  
x1 x10 Off 12dB 24dB  
Low  
95  
r
Filter Type  
75  
60  
50  
Filter Freq. (Hz)  
130  
i 24dBwꢍꢀ$POGJHVSFTꢀUIFꢀGJMUFSꢀGPSꢀ$)ꢀꢂꢎꢅꢀ  
to attenuate frequencies above or below the  
selected filter frequency at a rate of 24 dB per  
PDUBWFꢀ -JOLXJU[ꢋ3JMFZꢀBMJHONFOUꢃꢌꢀ  
e
he  
nput  
to  
200  
hen  
ed.  
|
|
LP BP HP  
500  
CH  
(Le  
of amplifier channels for maximum clean  
output, please refer to Appendix B (page 22)  
in this manual. After using this procedure,  
you can then adjust the relative level of each  
channel pair by adjusting the input sensitivity  
downward on either or both channel pairs, if  
they require attenuation to achieve the desired  
TZTUFNꢀCBMBODFꢌꢀ%PꢀOPUꢀJODSFBTFꢀUIFꢀiInput  
Sens.wꢀTFUUJOHꢀGPSꢀBOZꢀBNQMJGJFSꢀJOꢀUIFꢀTZTUFNꢀ  
beyond the maximum level established during  
the procedure outlined in Appendix B (page  
ꢅꢅꢃꢌꢀ%PJOHꢀTPꢀXJMMꢀSFTVMUꢀJOꢀBVEJCMFꢀEJTUPSUJPOꢀ  
and possible speaker damage. Be aware that  
CPUIꢀiInput Sens.wꢀBEKVTUNFOUTꢀXJMMꢀIBWFꢀUPꢀCFꢀ  
made, regardless of how many input cables are  
feeding the amplifier. These controls will allow  
you to set the appropriate relative levels for CH  
1&2 relative to CH 3&4 and other amplifier  
channels in the system.  
1)iFilter Typewꢀ$POUSPMꢍꢀ-PDBUFEꢀJOꢀUIF  
ꢀiCH 1&2 Filter SectionwꢁꢀꢀUIJTꢀTXJUDIꢀBMMPXTꢀ  
you to configure the CH 1&2 filter into one  
of three filter types:  
%FQFOEJOHꢀPOꢀUIFꢀTQFBLFSꢀTZTUFNꢀBOEꢀ  
the vehicle, different filter slopes may be  
required to produce a smooth transition  
between the sound of different speakers in the  
system. Experiment to find the slope which  
best matches the acoustic requirements of  
UIFꢀTZTUFNꢌꢀ5IFꢀTIBSQFSꢀi24dBwꢀTFUUJOHꢀXJMMꢀ  
do a better job of protecting small speakers  
with limited power handling. The shallower  
i12dBwꢀPDUBWFꢀTFUUJOHꢀBMMPXTꢀUIFꢀSFBSꢀTQFBLFSTꢀ  
to reproduce more low-frequency content.  
i 12dBwꢍꢀ$POGJHVSFTꢀUIFꢀIJHIꢋQBTTꢀGJMUFSꢀGPSꢀ$)ꢀ  
3&4 to attenuate frequencies below the selected  
filter frequency at a rate of 12 dB per octave  
(Butterworth alignment).  
i LPwꢀ Low-Pass): Configures the CH 1&2  
filter to attenuate frequencies above  
the selected filter frequency. Useful  
for connection of subwoofer(s) to CH  
1&2 in a bi-amplified system.  
i 24dBwꢍꢀ$POGJHVSFTꢀUIFꢀIJHIꢋQBTTꢀGJMUFSꢀGPSꢀ$)ꢀ  
3&4 to attenuate frequencies below the selected  
filter frequency at a rate of 24 dB per octave  
-JOLXJU[ꢋ3JMFZꢀBMJHONFOUꢃꢌꢀ  
%FQFOEJOHꢀPOꢀUIFꢀTQFBLFSꢀTZTUFNꢀBOEꢀUIFꢀ  
vehicle, different filter slopes may be required to  
produce a smooth transition between the speakers  
in the system. Experiment to find the slope  
which best matches the acoustic requirements  
PGꢀZPVSꢀTZTUFNꢌꢀ5IFꢀTIBSQFSꢀi24dBwꢀTFUUJOHꢀ  
will do a better job of protecting small speakers  
with limited power handling. The shallower  
i12dBwꢀPDUBWFꢀTFUUJOHꢀBMMPXTꢀUIFꢀSFBSꢀTQFBLFSTꢀUPꢀ  
reproduce more low-frequency content.  
i BPwꢀ #BOEQBTTꢃꢍꢀ$POGJHVSFTꢀUIFꢀGJMUFSꢀUPꢀ  
attenuate frequencies above the selected filter  
frequency and below the frequency selected  
in the CH 3&4 High-Pass Filter. This creates  
a true bandpass filter well-suited for driving  
mid-bass or mid-range speakers in a tri-  
amplified system.  
3) i Freq. RangFwꢀ$POUSPMꢍꢀ8IFOꢀUISPXOꢀUPꢀ  
the right, this switch multiplies the cutoff  
GSFRVFODZꢀTFMFDUFEꢀCZꢀUIFꢀSPUBSZꢀiFilter Freq.  
(Hz)wꢀDPOUSPMꢀCZꢀBꢀGBDUPSꢀPGꢀꢂꢈꢌꢀ*OꢀUIFꢀix1wꢀ  
position, the range of the rotary control is  
ꢇꢈꢀꢋꢀꢇꢈꢈꢀ)[ꢀ BTꢀNBSLFEꢃꢌꢀ*OꢀUIFꢀix10wꢀ  
position, the range of the rotary control is  
ꢇꢈꢈꢀ)[ꢀꢋꢀꢇꢀL)[ꢀ ꢇꢈꢈꢈꢀ)[ꢃꢌ  
i HPwꢀ High-Pass): Configures the CH 1&2  
filter to attenuate frequencies below the  
selected filter frequency. Useful for connection  
of component speakers to CH 1&2 in a bi-  
amplified system.  
4)iFilter Freq. (Hz)wꢀ5IFꢀGJMUFSꢀGSFRVFODZꢀ  
markings surrounding this rotary control  
are for reference purposes and are generally  
accurate to within 1/3 octave or better. If you  
would like to select the filter cutoff frequency  
with a higher level of precision, consult the  
charts in Appendix A (page 22) of this manual.  
2) iFreq. Rangewꢀ$POUSPMꢍꢀ8IFOꢀUISPXOꢀUPꢀUIFꢀ  
right, this switch multiplies the cutoff frequency  
TFMFDUFEꢀCZꢀUIFꢀSPUBSZꢀiFilter Freq. (Hz)wꢀ  
DPOUSPMꢀCZꢀBꢀGBDUPSꢀPGꢀꢂꢈꢌꢀ*OꢀUIFꢀix1wꢀQPTJUJPOꢁꢀ  
UIFꢀSBOHFꢀPGꢀUIFꢀSPUBSZꢀDPOUSPMꢀJTꢀꢇꢈꢀꢋꢀꢇꢈꢈꢀ)[ꢀ BTꢀ  
NBSLFEꢃꢌꢀ*OꢀUIFꢀix10wꢀQPTJUJPOꢁꢀUIFꢀSBOHFꢀPGꢀUIFꢀ  
SPUBSZꢀDPOUSPMꢀJTꢀꢇꢈꢈꢀ)[ꢀꢋꢀꢇꢀL)[ꢀ ꢇꢈꢈꢈꢀ)[ꢃꢌ  
8 | JL Audio - 450/4v2 Owner’s Manual  
9
 
SPEAKER OUTPUTS  
3)iFilter Freq. (Hz)wꢀ5IFꢀGJMUFSꢀGSFRVFODZꢀ  
markings surrounding this rotary control  
are for reference purposes and are generally  
accurate to within 1/3 octave or better. If you  
would like to select the filter cutoff frequency  
with a higher level of precision, consult the  
charts in Appendix A (page 22) of this manual.  
3) iALLwꢍꢀ5IJTꢀNPEFꢀEFMJWFSTꢀBꢀTVNꢀPGꢀUIFꢀTJHOBMTꢀ  
CFJOHꢀGFEꢀUPꢀUIFꢀiCH 1&2 Input SectionwꢀBOEꢀ  
iCH 3&4 Input SectionwꢀPGꢀUIFꢀBNQMJGJFSꢌꢀ  
1) iInfrasonic Filterwꢍꢀ5IFꢀJOGSBTPOJDꢀGJMUFSꢀJTꢀBꢀ  
24 dB/octave high-pass filter, with a fixed  
DVUPGGꢀGSFRVFODZꢀPGꢀꢏꢈꢀ)[ꢌꢀ5IJTꢀGJMUFSꢀJTꢀ  
designed to conserve amplifier power and  
protect subwoofer systems without audibly  
degrading the sub-bass output. 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. The  
infrasonic filter can be completely defeated  
CZꢀTFMFDUJOHꢀUIFꢀiOffwꢀQPTJUJPOꢀPOꢀUIFꢀ  
iInfrasonic FilterwꢀTXJUDIꢌꢀ5IJTꢀCZQBTTFTꢀBMMꢀ  
signal from flowing through the circuit.  
The 450/4v2 employs JL Audio’s exclusive  
Regulated, Intelligent Power Supply (R.I.P.S.)  
design. The operation of the R.I.P.S. system is  
independent for each pair of channels. This  
sophisticated power supply allows the amplifier  
to produce its optimum power (150 watts x 2 for  
channels 1&2 and 75 watts x 2 for channels 3&4)  
over a wide range of speaker impedances.  
Unlike conventional amplifiers that require  
a specific impedance to produce optimum  
power, the R.I.P.S.-equipped 450/4v2 gives  
you the freedom to use a variety of speaker  
configurations that achieve final nominal  
impedances between 1.5 – 4Ω per channel in  
stereo (without sacrificing power output or  
sound quality). When bridged, each channel  
QBJSꢀXJMMꢀPQUJNJ[FꢀPVUQVUꢀCFUXFFOꢀꢏꢀoꢀꢑ͙ꢌꢀ  
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  
JNQFEBODFꢀPQUJNJ[BUJPOꢁꢀDIPPTJOHꢀUIFꢀTUBHFꢀ  
most appropriate to the actual impedance of the  
speakers you connect to it.  
The Preamp Output signal is not affected by  
UIFꢀiLF BoostwꢀPSꢀiInfrasonic FilterwꢀQSPDFTTJOHꢀ  
selected for the amplifier or by any crossover  
filter selected (if the input signal is full-range,  
the preamp output will be full-range). When  
the 450/4v2 is being used to drive front and  
rear speaker systems, this preamp output mode  
will deliver a summed front/rear signal to the  
subwoofer amplifier, while permitting fading  
of the front and rear speaker systems from the  
source unit.  
Preamp Output Section  
The 450/4v2 incorporates a pass-through  
preamp output section, so that additional  
amplifiers can be added to the system. This pass-  
through pre-amp output can be configured three  
EJGGFSFOUꢀXBZTꢀVTJOHꢀUIFꢀTXJUDIꢀMBCFMFEꢀiSignal  
FromwꢀJOꢀUIFꢀiPreamp Output Sectionwꢌ  
Preamp Output Section  
CH 1  
Noteꢍꢀ5IFꢀTJHOBMꢀMFWFMꢀPGꢀUIFꢀiPreamp Outputwꢀ  
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. A JL Audio amplifier receiving  
signal from this preamp output should have  
its “Input Range” switch set to “Low”.  
Signal From  
2)iBass EQwꢍꢀ5IJTꢀTXJUDIꢀBMMPXTꢀUIFꢀVTFSꢀUPꢀ  
BDUJWBUFꢀBꢀꢐꢀE#ꢀCPPTUꢀDFOUFSFEꢀBUꢀꢆꢑꢀ)[ꢌ  
|
|
1 & 2 3 & 4 All  
3)iRemote Bass Portwꢍꢀꢀ"MMPXTꢀZPVꢀUPꢀDPOOFDUꢀBOꢀ  
optional remote boost knob (sold separately,  
JL Audio Model RBC-1) that can be mounted  
in the front of the vehicle. With the RBC-1  
connected, the boost is no longer limited to 0  
or +6 dB, allowing a range of 0-15 dB of boost  
to be selected.  
1
Left Output Right Output  
B
CH 1 & 2 Bass Control  
1) i 1&2wꢍꢀ5IFꢀQSFBNQꢀPVUQVUꢀEFMJWFSTꢀUIFꢀTBNFꢀ  
signal that is connected to the 450/4v2’s  
CH 1&2 Inputs. This mode is useful for  
feeding a subwoofer amplifier when the  
450/4v2 is being used to drive front and rear  
speaker systems. This preamp output mode  
will track the signal level of CH 1&2, allowing  
fading of the rear channels without affecting  
the subwoofer level.  
This section provides two basic bass processing  
tools for CH 1&2: a 24 dB/octave infrasonic filter  
BUꢀꢏꢈꢀ)[ꢀBOEꢀBꢀꢄꢐꢀE#ꢀCPPTUꢀDJSDVJUꢀDFOUFSFEꢀBUꢀꢆꢑꢀ  
)[ꢌꢀꢀ"DUJWBUJPOꢀPGꢀFJUIFSꢀGFBUVSFꢀBVUPNBUJDBMMZꢀ  
sums the CH 1&2 input signals to mono. (These  
features should only be used when driving  
subwoofer(s) from CH 1&2).  
ction  
CH 1 & 2 Speaker Outputs  
CH  
Ba  
IMPORTANT  
!
O
The “Bass EQ” and “Infrasonic Filter” features  
will only operate when the CH 1&2 filter is  
activated and in low-pass mode. If you are  
using an external active crossover and would  
like to use the “Bass EQ” and “Infrasonic  
Filter” features, set the “Filter Mode/Slope”  
switch on “12dB” and rotate the frequency  
selection knob fully clockwise to the “500 Hz”  
position. This will activate the bass controls  
without significantly affecting the crossover  
point selected by the external active crossover.  
Left  
150W  
Right  
150W  
(1.5-4Ω)  
uts  
CH 1 & 2 Bass Control  
CH 1  
Re  
Ba  
utput  
Bridged: 300W x 1 (3-8Ω)  
Bass EQ  
Infrasonic Filter  
Freq.  
|
|
Off On  
Off 30Hz  
x1  
75  
2) i 3&4wꢍꢀ5IFꢀQSFBNQꢀPVUQVUꢀEFMJWFSTꢀUIFꢀTBNFꢀ  
signal that is connected to the 450/4v2’s CH  
3&4 Inputs. This mode is useful for feeding a  
subwoofer amplifier when the 450/4v2 is being  
used to drive front and rear speaker systems.  
This preamp output mode will track the signal  
level of CH 3&4, allowing fading of the front  
channels without affecting the subwoofer level.  
Either  
feature  
sums the  
CH 1&2 input  
signals to  
mono when  
activated.  
60  
50  
Remote  
Bass Port  
Filter F  
10 | JL Audio - 450/4v2 Owner’s Manual  
11  
 
IMPORTANT  
!
BRIDGING CONSIDERATIONS  
STATUS INDICATOR LIGHTS /  
PROTECTION CIRCUITRY  
There are three status indicator lights on the  
top of the amplifier. These are as follows:  
SERVICING YOUR JL AUDIO AMPLIFIER  
If your amplifier fails or malfunctions, please  
SFUVSOꢀJUꢀUPꢀZPVSꢀBVUIPSJ[FEꢀ+-ꢀ"VEJPꢀEFBMFSꢀTPꢀ  
that it may be sent in to JL Audio for service.  
There are no user serviceable parts or fuses inside  
the amplifier. The unique nature of the circuitry  
in the JL Audio amplifiers requires specifically  
USBJOFEꢀTFSWJDFꢀQFSTPOOFMꢌꢀ%PꢀOPUꢀBUUFNQUꢀ  
to service the amplifier yourself or through  
VOBVUIPSJ[FEꢀSFQBJSꢀGBDJMJUJFTꢌꢀ5IJTꢀXJMMꢀOPUꢀPOMZꢀ  
void the warranty, but may result in the creation  
of more problems within the amplifier.  
If you connect a load higher than 4Ω nominal  
per channel in stereo mode (or 8Ω in bridged  
mode), power will drop by half with every  
doubling of impedance above 4Ω stereo / 8Ω  
mono. If you connect a load lower than 1.5Ω  
nominal per channel in stereo mode (or 3Ω in  
bridged mode, the amplifier protection  
circuitry activates a “safe” mode which reduces  
amplifier power to protect the circuitry from  
failure (the yellow “Low Ω” LED lights to  
indicate that this has happened). See page 13  
for details.  
Bridging is the practice of combining the  
output of two amplifier channels to drive a single  
load. When bridged, each channel produces  
signals of equal magnitude, but opposite polarity.  
The combined output of the two channels  
provides twice the output voltage available from a  
single channel. The 450/4v2 has been designed for  
bridging of its channel pairs without the need for  
input inversion adaptors.  
1)iPowerwꢀ Green): lights to indicate that the  
amplifier is turned on and operating normally.  
2)iThermalwꢀ Red): lights to indicate that the  
amplifier has exceeded its safe operating  
temperature, putting the amplifier into a self-  
protection mode, which reduces the power  
output of the amplifier. The red light will shut  
off and the amplifier will return to normal,  
full-power operating mode if the heat sink  
temperature drops back to a safe level.  
ction  
CH 3 & 4 Speaker Outputs  
Sens.  
IMPORTANT  
!
Left  
75W  
Right  
75W  
(1.5-4Ω)  
Speaker loads below 1.5Ω nominal per channel  
in stereo or 3Ω nominal in bridged mode are  
not recommended and may cause the amplifier  
output to distort excessively.  
If you have any questions about the installation or  
setup of the amplifier not covered in this manual,  
please contact your dealer or technical support.  
H 4  
ght)  
Bridged: 150W x 1 (3-8Ω)  
3)iLow Ωwꢀ Amber): lights to indicate that the  
impedance of the speaker load connected to  
the amplifier is lower than the optimum load  
impedance range for the amplifier. When  
this light is on, a protection circuit engages  
and reduces the power output of CH 1&2  
or CH 3&4, depending on which channel is  
experiencing the problem. The amber indicator  
will also light when a short-circuit is detected  
in the speaker wiring (this can be a short  
between the positive and negative speaker  
wires or between either speaker wire and the  
vehicle chassis). This can be used to diagnose  
a short-circuit by only connecting one of the  
amplifier sections at a time (CH 1&2 and CH  
ꢏꢎꢆꢃꢌꢀ5IFꢀBNCFSꢀ-&%ꢀXJMMꢀMJHIUꢀXIFOꢀZPVꢀ  
connect the section that is experiencing the  
problem and turn the volume up.  
5PꢀCSJEHFꢀBꢀQBJSꢀPGꢀDIBOOFMTꢁꢀVTFꢀUIFꢀiLeft +wꢀ  
BOEꢀiRight –wꢀTQFBLFSꢀDPOOFDUPSTꢀPOMZꢀ UIFꢀiLeft  
wꢀBOEꢀiRight +wꢀSFNBJOꢀVOVTFEꢃꢌꢀ5IFOꢀDPOOFDUꢀ  
a mono signal to both left and right RCA inputs  
for that channel pair. This requires an RCA  
i:ꢋ"EBQUPSwꢀꢀMJLFꢀUIFꢀ+-ꢀ"VEJPꢀ&$4ꢀNPEFMꢀ  
XB-CLRAICY-1F2M (sold separately).  
JL Audio Technical Support:  
(954) 443-1100  
9:00 AM – 5:30 PM (Eastern Time Zone)  
Monday - Friday  
When bridged, each channel pair will  
deliver optimum power into a 3-8Ω load.  
Operating bridged channel pairs into a load  
lower than 3Ω is not recommended.  
Because a bridged pair of channels requires  
that both channels receive input, you need to  
connect both left and right RCA inputs to the  
bridged channel pair’s inputs. Connection of  
only one RCA input will result in reduced power  
output, increased distortion and can cause the  
BNQMJGJFSꢀUPꢀPWFSIFBUꢌꢀ%PꢀOPUꢀEPꢀUIJTꢒꢀ*OTUFBEꢁꢀVTFꢀ  
Bꢀi:ꢋBEBQUPSwꢀUPꢀTQMJUꢀUIFꢀNPOPꢀTJHOBMꢀJOUPꢀCPUIꢀ  
left and right RCA inputs.  
There is only one condition that will shut  
down an undamaged 450/4v2 completely…  
If battery voltage drops below 10 volts, the  
entire amplifier will shut itself off. The green  
i1PXFSwꢀJOEJDBUPSꢀPOꢀUIFꢀUPQꢀPGꢀUIFꢀBNQMJGJFSꢀXJMMꢀ  
turn off when this occurs. The amplifier will turn  
back on when voltage climbs back above 10 volts.  
This may happen in a rapid cycle when bass-  
heavy program material causes a weak charging  
system to dip below 10 volts momentarily. If this  
is happening in your system, have your charging  
system inspected to make sure it is working  
properly. For information on troubleshooting this  
amplifier, refer to Appendix C (page 24).  
12 | JL Audio - 450/4v2 Owner’s Manual  
13  
 
SYSTEM CONFIGURATIONS  
The 450/4v2 is a very flexible amplifier, well-  
suited for a multitude of system configurations.  
In this section, the most likely configurations are  
explained in detail.  
Once you have selected your desired  
configuration, you can use the amplifier panel  
drawings on the bottom of the following  
pages to mark the required switch positions for  
easy reference.  
B) Fade Subwoofer Level vs. HF Level  
Required: a source unit or processor with front  
and rear pairs of outputs.  
Crossover Setup for Bi-Amplified System  
with one 450/4v2:  
The separate amplifier will drive the subwoofer  
system with low-pass filtering (select a filter  
GSFRVFODZꢀPGꢀꢑꢈꢋꢓꢈꢀ)[ꢀUPꢀTUBSUꢃꢌꢀ5IFꢀJOQVUTꢀPGꢀUIFꢀ  
subwoofer amplifier may or may not be connected  
to the preamp outputs of the 450/4v2, depending  
on which connection option you choose.  
Input Connections: the first stereo pair of source  
unit outputs is connected to the CH 1&2  
inputs of the 450/4v2. The second stereo pair  
of source unit outputs is connected to the CH  
ꢏꢎꢆꢀJOQVUTꢀ TFMFDUꢀi4chwꢀPOꢀUIFꢀiInput Modewꢀ  
TXJUDIꢀJOꢀUIFꢀiCH 1&2 Input Sectionwꢃꢌꢀ  
Result: in this mode, the user has the ability to  
fade or control the level of the LF channels  
relative to the HF channels via the source  
unit’s fader control without exceeding the  
maximum clean output level set by each  
BNQMJGJFSꢀTFDUJPOꢊTꢀiInput Sens.wꢀDPOUSPMTꢌ  
Once the input sections have been  
DPOGJHVSFEꢀBQQSPQSJBUFMZꢁꢀHPꢀUPꢀUIFꢀiCH 1&2  
Filter Sectionwꢌꢀꢀ4FMFDUꢀix1wꢀPOꢀUIFꢀiFreq.  
RangewꢀTXJUDIꢁꢀiLPwꢀ MPXꢋQBTTꢃꢀPOꢀUIFꢀiFilter  
TypewꢀTXJUDIꢀBOEꢀi12dBwꢀPSꢀi24dBwꢀPOꢀUIFꢀ  
iFilter Mode/SlopewꢀTXJUDIꢀBOEꢀBOꢀBQQSPQSJBUFꢀ  
iFilter Freqꢌwꢀ ꢑꢈꢋꢓꢈꢀ)[ꢀJTꢀBꢀHPPEꢀTUBSUJOHꢀ  
point). You may also choose to activate the  
iInfrasonic FilterwꢀBOEꢉPSꢀiBass EQwꢀGFBUVSFTꢀ  
JOꢀUIFꢀiCH 1&2 Bass ControlwꢀTFDUJPOꢌꢀ1MFBTFꢀ  
LFFQꢀJOꢀNJOEꢀUIBUꢀBDUJWBUJPOꢀPGꢀUIFꢀiBass EQwꢀ  
NBZꢀSFRVJSFꢀMPXFSJOHꢀUIFꢀ$)ꢀꢂꢎꢅꢀiInput  
SensꢌwꢀUPꢀNBJOUBJOꢀDMFBOꢀNBYJNVNꢀPVUQVUꢌ  
/FYUꢁꢀUVSOꢀZPVSꢀBUUFOUJPOꢀUPꢀUIFꢀiCH  
3&4 Input SectionwꢀBOEꢀTFMFDUꢀix1wꢀPOꢀUIFꢀ  
iFreq. RangewꢀTXJUDIꢁꢀiHPwꢀ IJHIꢋQBTTꢃꢀ  
POꢀUIFꢀiFilter TypewꢀTXJUDIꢀBOEꢀi12dBwꢀPSꢀ  
i24dBwꢀPOꢀUIFꢀiFilter Mode/SlopewꢀTXJUDIꢀ  
BOEꢀBOꢀBQQSPQSJBUFꢀiFilter Freq.wꢀ BHBJOꢁꢀ  
ꢑꢈꢋꢓꢈꢀ)[ꢀJTꢀBꢀHPPEꢀTUBSUJOHꢀQPJOUꢃꢌ  
Input connection options for a bi-amplifier  
system with one 450/4v2 and a separate subwoofer  
amplifier are as follows:  
BI-AMPLIFIED SYSTEMS  
Bi-amplified systems are defined as systems  
in which separate amplifier channels drive low-  
frequency (LF) and high-frequency (HF) speakers  
and are separately filtered to send appropriate  
frequency ranges to each speaker system.  
The most common application of bi-  
amplification in mobile audio is to drive a  
subwoofer system from one or more amplifiers or  
channels and component speakers from separate  
amplifiers or channels.  
A) No User Adjustability  
Required: a basic source unit or processor with  
left and right stereo outputs.  
Input Connections: a single pair of stereo source  
unit outputs is connected to the CH 1&2  
JOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi2chwꢀPOꢀUIFꢀ  
iInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2 Input  
Sectionwꢃꢌꢀ$POOFDUꢀUIFꢀTVCXPPGFSꢀBNQMJGJFSꢀ  
inputs to the preamp outputs of the 450/4v2  
4FMFDUꢀi1&2wꢀPOꢀUIFꢀi4JHOBMꢀ'SPNwꢀTXJUDIꢀJOꢀ  
UIFꢀiPreamp Output Sectionwꢃꢌꢀ  
Result: the relative level of the LF and front and  
rear HF channels will be fixed by the 450/4v2’s  
iInput Sens.wꢀTFUUJOHTꢀBOEꢀXJMMꢀOPUꢀCFꢀVTFSꢀ  
adjustable from the front of the vehicle.  
C) Subwoofer Level Control Only  
Required: a source unit or processor with left,  
right and subwoofer outputs.  
Input Connections: the main stereo pair of source  
unit outputs is connected to the CH 3&4 inputs  
of the 450/4v2. The source unit’s dedicated  
subwoofer output is connected to the CH  
ꢂꢎꢅꢀJOQVUTꢀ TFMFDUꢀi4chwꢀPOꢀUIFꢀiInput Modewꢀ  
TXJUDIꢀJOꢀUIFꢀiCH 1&2 Input Sectionwꢃꢌꢀꢀ  
Result: in this mode, the user has the ability to  
control the absolute level of the LF channels  
relative to the HF channels.  
The 450/4v2 can be configured to drive a  
bi-amplified system by itself or with a separate  
subwoofer amplifier.  
After proper adjustment of the CH  
ꢂꢎꢅꢀBOEꢀ$)ꢀꢏꢎꢆꢀiInput RangewꢀBOEꢀ  
Bi-Amplified System with one 450/4v2  
In this configuration, CH 1&2 of the 450/4v2  
will drive subwoofers (stereo 150W x 2 or bridged  
300W x 1) with low-pass filtering. CH 3&4 will  
drive component speakers in stereo (75W x 2)  
with high-pass filtering.  
iInput Sens.wꢀDPOUSPMTꢀVTJOHꢀUIFꢀNFUIPEꢀ  
shown in Appendix B (page 22), you can  
fine tune filter frequencies and slopes and  
attenuate either pair of channels to achieve  
proper balance. For precise filter frequency  
information refer to Appendix A (page 22).  
B) Fade Subwoofer Level vs. HF Level  
Required: a source unit or processor with front  
and rear pairs of stereo outputs.  
IMPORTANT  
!
Input Connections: one stereo pair of source  
unit outputs is connected to the CH 1&2  
JOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi2chwꢀPOꢀUIFꢀ  
iInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2 Input  
Sectionwꢃꢌꢀ5IFꢀTFDPOEꢀTUFSFPꢀQBJSꢀPGꢀTPVSDFꢀ  
unit outputs is connected to the subwoofer  
amplifier inputs. In this mode, the 450/4v2’s  
preamp output is not used.  
Set the CH 1&2 “Input Sens.” with the source  
unit’s subwoofer level control set at 3/4 of full  
output. See Appendix B (page 22) for details.  
Input connection options for a bi-amplified system  
with one 450/4v2 are as follows:  
Bi-Amplified System with one  
450/4v2 in four-channel mode and  
a separate subwoofer amplifier  
A) No User Adjustability  
Required: a basic source unit or processor with  
left and right stereo outputs.  
This configuration requires that  
the separate subwoofer amplifier has  
a built-in low-pass filter. All JL Audio  
subwoofer amplifiers have this feature.  
In this configuration, CH 1&2 of the 450/4v2  
will drive front component speakers (stereo 150W  
x 2) with high-pass filtering. CH 3&4 will drive  
rear component speakers in stereo (75W x 2) with  
high-pass filtering.  
Input Connections: a single pair of stereo source  
unit outputs connected to the CH 1&2 inputs of  
UIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi2chwꢀPOꢀUIFꢀiInput Modewꢀ  
TXJUDIꢀJOꢀUIFꢀiCH 1&2 Input Sectionwꢃꢌꢀ  
Result: the relative level of the LF and HF  
DIBOOFMTꢀXJMMꢀCFꢀGJYFEꢀCZꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢊTꢀiInput  
Sens.wꢀTFUUJOHTꢀBOEꢀXJMMꢀOPUꢀCFꢀVTFSꢀBEKVTUBCMFꢀ  
from the front of the vehicle.  
Result: with this option, the user has the ability  
to fade the level of the subwoofer amplifier’s  
input relative to the HF channels, but  
cannot control front-to-rear fading of the  
HF channels. The relative level of the front and  
rear HF channels will be fixed by the 450/4v2’s  
iInput Sens.wꢀTFUUJOHTꢀBOEꢀXJMMꢀOPUꢀCFꢀVTFSꢀ  
adjustable from the front of the vehicle.  
14 | JL Audio - 450/4v2 Owner’s Manual  
15  
 
C) Fade HF Front to Rear with Non-Fading  
Subwoofer Level  
Required: a source unit or processor with front  
and rear pairs of stereo outputs.  
E) Front to Rear HF Fading and  
Subwoofer Level Control  
Required: a source unit or processor with  
front and rear pairs of stereo outputs plus a  
dedicated subwoofer output.  
After proper adjustment of the 450/4v2’s CH  
1&2 and CH 3&4, and the subwoofer amplifier’s  
iInput RangewꢀBOEꢀiInput Sens.wꢁꢀZPVꢀDBOꢀGJOFꢀ  
tune filter frequencies and slopes and attenuate  
either pair of channels to achieve proper balance.  
'PSꢀQSPQFSꢀBEKVTUNFOUꢀPGꢀUIFꢀiInput Sens.wꢀ  
controls of the 450/4v2 use the method shown in  
Appendix B (page 22). For precise filter frequency  
information for the 450/4v2 refer to Appendix  
A (page 22). Refer to the subwoofer amplifier  
owner’s manual for proper adjustments.  
Input connection options for bi-amplified 3.1  
system with one 450/4v2 and a separate subwoofer  
amplifier:  
Input Connections: one stereo pair of source  
unit outputs-is connected to the CH 1&2  
JOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi4chwꢀPOꢀUIFꢀ  
iInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2 Input  
Sectionwꢃꢌꢀ5IFꢀTFDPOEꢀTUFSFPꢀQBJSꢀPGꢀTPVSDFꢀ  
unit outputs is connected to the CH 3&4  
inputs of the 450/4v2. Connect the subwoofer  
amplifier inputs to the preamp outputs of the  
ꢆꢇꢈꢉꢆWꢅꢀ 4FMFDUꢀiALLwꢀPOꢀUIFꢀiSignal Fromwꢀ  
TXJUDIꢀJOꢀUIFꢀiPreamp Output Sectionwꢃꢌꢀ  
Result: with this option, the user has the ability to  
fade the HF signals from front-to-rear without  
fading the signal to the subwoofer amplifier.  
A) Real Left-Center-Right Channels and  
Subwoofer with Multi-Channel Source  
Required: a multi-channel processor or source  
VOJUꢀ %PMCZꢀ%JHJUBM¥ꢁꢀ%PMCZꢀ1SP-PHJDꢀ**¥ꢁꢀEUT¥ꢁꢀ  
etc.) with center channel output.  
Input Connections: one stereo pair (front,  
typically) of source unit outputs is connected  
to the CH 1&2 inputs of the 450/4v2. The  
second stereo pair of source unit outputs  
(rear, typically) is connected to the CH  
ꢏꢎꢆꢀJOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi4chwꢀPOꢀ  
UIFꢀiInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2  
Input Sectionwꢃꢌꢀ5IFꢀTPVSDFꢀVOJUꢊTꢀEFEJDBUFEꢀ  
subwoofer output is connected to the  
subwoofer amplifier inputs. In this mode, the  
450/4v2’s preamp output is not used.  
Result: with this option, the user has the ability  
to fade the front and rear HF channels relative  
to each other and also has the ability to  
control the absolute level of the subwoofer  
channel relative to the HF channels.  
Input Connections: the left-front and right-front  
source unit outputs are connected to the CH  
1&2 inputs of the 450/4v2 and the front-center  
channel output of the source unit or processor  
is connected to the CH 3&4 inputs of the  
ꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi4chwꢀPOꢀUIFꢀiInput Modewꢀ  
TXJUDIꢀJOꢀUIFꢀiCH 1&2 Input Sectionwꢃꢌꢀ6TFꢀBꢀ  
i:ꢋBEBQUPSwꢀMJLFꢀUIFꢀ+-ꢀ"VEJPꢀ&$4ꢀNPEFMꢀ9#ꢋ  
CLRAICY-1F2M (sold separately) to feed both  
RCA jacks on the amplifier from the single  
signal cable. Most multi-channel processors  
and source units are also equipped with a  
dedicated subwoofer output and subwoofer  
level control. Connect this subwoofer output  
directly to the subwoofer amplifier’s inputs.  
The 450/4v2’s preamp outputs are not used.  
Result: True left, center and right channels with  
multi-channel material, derived center channel  
with stereo material. Rear-surround channels  
are unused. User adjustability of left, center  
and right channels depends on source unit/  
processor. Subwoofer level is user adjustable.  
Bi-Amplified 3.1 System with one 450/4v2  
in three-channel mode and a separate  
subwoofer amplifier  
This configuration requires a separate  
subwoofer amplifier with a built-in low-  
pass filter. All JL Audio subwoofer  
D) Subwoofer Level Control Only  
amplifiers have this feature.  
Required: a source unit or processor with left,  
right and dedicated subwoofer outputs.  
Input Connections: The main stereo pair of  
source unit outputs is connected to the CH  
ꢂꢎꢅꢀJOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi2chwꢀPOꢀ  
UIFꢀiInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2  
Input Sectionwꢃꢌꢀ5IFꢀTPVSDFꢀVOJUꢊTꢀEFEJDBUFEꢀ  
subwoofer output is connected to the  
The separate amplifier will drive the subwoofer  
system with low-pass filtering (select a filter  
GSFRVFODZꢀPGꢀꢑꢈꢋꢓꢈꢀ)[ꢀUPꢀTUBSUꢃꢌꢀ5IFꢀJOQVUTꢀPGꢀ  
the subwoofer amplifier will be connected to the  
preamp outputs of the 450/4v2 or to the source  
unit or multi-channel processor directly.  
In this configuration, CH 1&2 of the 450/4v2  
will drive front-left and front-right component  
speakers (stereo 150W x 2) with high-pass  
filtering. CH 3&4 will be bridged mono to drive a  
center-front component speaker system (150W x  
1) with high-pass filtering. All three channels will  
have equal power at 3 – 4Ω.  
IMPORTANT  
!
Set the CH 1&2 “Input Sens.” with the source  
unit’s subwoofer level control set at 3/4 of full  
output. See Appendix B (page 20) for details.  
subwoofer amplifier inputs. In this mode, the  
450/4v2’s preamp output is not used.  
Crossover Setup for Bi-Amplified System with one  
450/4v2 and a separate subwoofer amplifier:  
Result: with this option, the user has the ability  
to control the absolute level of the subwoofer  
channel relative to the HF channels, but  
cannot fade the front and rear HF channels  
relative to each other.  
Once the input and preamp output sections  
have been configured appropriately, go to the  
iCH 1&2 Filter Sectionwꢌꢀ4FMFDUꢀix1wꢀPOꢀUIFꢀ  
iFreq. RangewꢀTXJUDIꢁꢀiHPwꢀ IJHIꢋQBTTꢃꢀPOꢀUIFꢀ  
i'JMUFSꢀ5ZQFwꢀTXJUDIꢀBOEꢀi12dBwꢀPSꢀi24dBwꢀPOꢀUIFꢀ  
i'JMUFSꢀMode/SlopFwꢀTXJUDIꢀBOEꢀBOꢀBQQSPQSJBUFꢀ  
iFilter Freq.wꢀ ꢑꢈꢋꢓꢈꢀ)[ꢀJTꢀBꢀHPPEꢀTUBSUJOHꢀQPJOUꢃꢌꢀꢀ  
5IFꢀiInfrasonic FilterwꢀBOEꢀiBass EQwꢀGFBUVSFTꢀ  
cannot be used in this mode.  
IMPORTANT  
!
Set the subwoofer amplifier’s “Input Sens.”  
with the source unit’s subwoofer level  
control set at 3/4 of full output. Refer to the  
subwoofer amplifier owner’s manual for  
proper adjustment.  
IMPORTANT  
!
Set the CH 1&2 “Input Sens.” with the source  
unit’s subwoofer level control set at 3/4 of full  
output. See Appendix B (page 20) for details.  
/FYUꢁꢀUVSOꢀZPVSꢀBUUFOUJPOꢀUPꢀUIFꢀiCH 3&4  
Input SectionwꢀBOEꢀTFMFDUꢀix1wꢀPOꢀUIFꢀiFreq.  
RangewꢀTXJUDIꢁꢀiHPwꢀ IJHIꢋQBTTꢃꢀPOꢀUIFꢀiFilter  
TypewꢀTXJUDIꢀBOEꢀi12dBwꢀPSꢀi24dBwꢀPOꢀUIFꢀiFilter  
Mode/SlopewꢀTXJUDIꢀBOEꢀBOꢀBQQSPQSJBUFꢀiFilter  
Freq.wꢀ BHBJOꢁꢀꢑꢈꢋꢓꢈꢀ)[ꢀJTꢀBꢀHPPEꢀTUBSUJOHꢀQPJOUꢃꢌ  
16 | JL Audio - 450/4v2 Owner’s Manual  
17  
 
IMPORTANT  
!
The “Summed Center Channel” methods  
outlined below do not create a true center  
channel, they simply sum left and right signals  
to the center speaker system. This is not as  
desirable as a true center channel from a multi-  
channel source, but it can be used to create a  
convincing sound stage in some applications.  
D) Fade Between “Summed Center Channel”  
Level and Left/Right Level with Separate  
Subwoofer Level Control  
Required: a source unit or processor with  
front and rear pairs of stereo outputs plus a  
dedicated subwoofer output.  
Crossover setup for bi-amplified 3.1 system with  
one 450/4v2 and a separate subwoofer amplifier:  
Bi-Amplified 5.1 System with  
Multi-Channel Source, one 450/4v2 in  
three-channel mode, a JL Audio 300/2  
amplifier driving rear surround speakers  
and a separate subwoofer amplifier  
(JL Audio 500/1v2 or 1000/1v2 recommended)  
This configuration is identical to the 3.1 system  
configuration with Input Option A, except for  
the addition of a JL Audio 300/2v2 two-channel  
amplifier to drive rear surround speakers,  
effectively creating a true 5.1 multi-channel  
system with left-front, center-front, right-front,  
left-rear and left-right channels.  
The 300/2v2 in two-channel stereo mode is  
perfectly matched to the 450/4v2 in three channel  
Left, Center, Right mode. The system will deliver  
150 W x 5 to power the component speaker  
systems plus the output of an additional amplifier  
to the subwoofer system.  
Once the input and preamp output sections have  
CFFOꢀDPOGJHVSFEꢀBQQSPQSJBUFMZꢁꢀHPꢀUPꢀUIFꢀiCH  
1&2 Filter Sectionwꢌꢀ4FMFDUꢀix1wꢀPOꢀUIFꢀiFreq.  
RangewꢀTXJUDIꢁꢀiHPwꢀ IJHIꢋQBTTꢃꢀPOꢀUIFꢀiFilter  
TypewꢀTXJUDIꢀBOEꢀi12dBwꢀPSꢀi24dBwꢀPOꢀUIFꢀ  
iFilter Mode/SlopewꢀTXJUDIꢀBOEꢀBOꢀBQQSPQSJBUFꢀ  
iFilter Freq.wꢀ ꢑꢈꢋꢓꢈꢀ)[ꢀJTꢀBꢀHPPEꢀTUBSUJOHꢀQPJOUꢃꢌꢀꢀ  
5IFꢀiInfrasonic FilterwꢀBOEꢀiBass EQwꢀGFBUVSFTꢀ  
cannot be used in this mode.  
/FYUꢁꢀUVSOꢀZPVSꢀBUUFOUJPOꢀUPꢀUIFꢀiCH 3&4  
Input SectionwꢀBOEꢀTFMFDUꢀix1wꢀPOꢀUIFꢀiFreq.  
RangewꢀTXJUDIꢁꢀiHPwꢀ IJHIꢋQBTTꢃꢀPOꢀUIFꢀiFilter  
TypewꢀTXJUDIꢀBOEꢀi12dBwꢀPSꢀi24dBwꢀPOꢀUIFꢀiFilter  
Mode/SlopewꢀTXJUDIꢀBOEꢀBOꢀBQQSPQSJBUFꢀiFilter  
Freq.wꢀ BHBJOꢁꢀꢑꢈꢋꢓꢈꢀ)[ꢀJTꢀBꢀHPPEꢀTUBSUJOHꢀQPJOUꢃꢌ  
After proper adjustment of the 450/4v2’s  
CH 1&2 and CH 3&4, and the subwoofer  
BNQMJGJFSꢊTꢀiInput RangewꢀBOEꢀiInput Sens.wꢁꢀ  
you can fine tune filter frequencies and slopes  
and attenuate the center channel or the left  
BOEꢀSJHIUꢀDIBOOFMꢀQBJSꢀXJUIꢀUIFꢀiInput Sens.wꢀ  
controls to achieve proper balance. For proper  
BEKVTUNFOUꢀPGꢀUIFꢀiInput Sens.wꢀDPOUSPMTꢀPGꢀUIFꢀ  
450/4v2 use the method shown in Appendix  
B (page 22). For precise filter frequency  
Input Connections: one pair of stereo source  
unit outputs is connected to the CH 1&2  
JOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi4chwꢀPOꢀUIFꢀ  
iInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2 Input  
Sectionwꢃꢌꢀ"ꢀTFDPOEꢀQBJSꢀPGꢀTPVSDFꢀVOJUꢀ  
outputs is connected to the CH 3&4 inputs.  
The source unit’s dedicated subwoofer output  
is connected to the subwoofer amplifier’s  
inputs. In this mode, the 450/4v2’s preamp  
output is not used.  
Result: with this option, the user has the ability to  
GBEFꢀCFUXFFOꢀUIFꢀi4VNNFEꢀ$FOUFSꢀ$IBOOFMwꢀ  
level and the Left and Right channel levels via  
the source unit’s fader control and also has  
the ability to control the absolute level of the  
subwoofer channel relative to the three HF  
channels with the source unit’s subwoofer  
level control.  
B) “Summed Center Channel”,  
No User Adjustability  
Required: a basic source unit or processor with  
left and right stereo outputs.  
Input Connections: a single pair of stereo source  
unit outputs, connected to the CH 1&2  
JOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi2chwꢀPOꢀUIFꢀ  
iInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2 Input  
Sectionwꢃꢌꢀ$POOFDUꢀUIFꢀTVCXPPGFSꢀBNQMJGJFSꢀ  
inputs to the preamp outputs of the 450/4v2  
4FMFDUꢀi1&2wꢀPOꢀUIFꢀiSignal FromwꢀTXJUDIꢀJOꢀ  
UIFꢀiPreamp Output Sectionwꢃꢌꢀ  
Result: the relative level of all channels will be  
GJYFEꢀCZꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢊTꢀiInput Sens.wꢀTFUUJOHTꢀ  
and will not be user adjustable from the front  
of the vehicle.  
To add this capability, connect the 300/2v2’s  
inputs to the rear (surround) outputs of a multi-  
channel processor or source unit and set the  
ꢏꢈꢈꢉꢅWꢅꢊTꢀiAmp FilterwꢀJOꢀiHPwꢀNPEFꢀXJUIꢀBꢀ  
i12dBwꢀPSꢀi24dBwꢀGJMUFSꢀTMPQFꢌꢀ  
C) Fade Between “Summed Center Channel”  
Level and Left/Right Level with Non-Fading  
Subwoofer Level  
Required: a source unit or processor with front  
and rear pairs of stereo outputs.  
Input Connections: one pair of stereo source  
unit outputs is connected to the CH 1&2  
JOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi4chwꢀPOꢀUIFꢀ  
iInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2 Input  
Sectionwꢃꢌꢀ"ꢀTFDPOEꢀQBJSꢀPGꢀTPVSDFꢀVOJUꢀ  
outputs is connected to the CH 3&4 inputs.  
Connect the subwoofer amplifier inputs to the  
QSFBNQꢀPVUQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ 4FMFDUꢀiALLwꢀ  
POꢀUIFꢀiSignal FromwꢀTXJUDIꢀJOꢀUIFꢀiPreamp  
Output Sectionwꢃꢌ  
IMPORTANT  
!
Set the subwoofer amplifier’s “Input Sens.”  
with the source unit’s subwoofer level  
control set at 3/4 of full output. Refer to the  
subwoofer amplifier owner’s manual for  
proper adjustment.  
information for the 450/4v2 refer to Appendix  
A (page 22). Refer to the subwoofer amplifier  
owner’s manual for proper adjustments.  
Result: with this option, the user has the ability  
UPꢀBEKVTUꢀUIFꢀSFMBUJWFꢀMFWFMꢀPGꢀUIFꢀi4VNNFEꢀ  
$FOUFSꢀ$IBOOFMwꢀJOQVUꢀSFMBUJWFꢀUPꢀUIFꢀ-FGUꢀBOEꢀ  
Right channel pair via the source unit’s fader  
control. Subwoofer is non-fading.  
18 | JL Audio - 450/4v2 Owner’s Manual  
19  
 
TRI-AMPLIFIED SYSTEMS  
Tri-amplified systems are defined as systems  
in which separate amplifier channels drive  
low-frequency (LF), mid-frequency (MF) and  
high-frequency (HF) speakers and are separately  
filtered to send appropriate frequency ranges to  
each speaker system.  
Input connection options for the Tri-Amplified  
Stereo mode are as follows:  
C) Subwoofer Level Control Only  
Required: a source unit or processor  
with left, right and dedicated  
Crossover setup for tri-amplified 3.1 system with  
one 450/4v2 and a separate subwoofer amplifier:  
A) No User Adjustability  
Required: a basic source unit or processor with  
left and right stereo outputs.  
subwoofer outputs is required.  
Once the input and preamp output sections have  
CFFOꢀDPOGJHVSFEꢀBQQSPQSJBUFMZꢁꢀHPꢀUPꢀUIFꢀiCH 1&2  
Filter SectionwꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢌꢀꢀ5IFTFꢀTFUUJOHTꢀ  
will determine the high-pass cutoff and slope of  
the bandpass filtering applied to the MF (mid-  
GSFRVFODZꢃꢀDIBOOFMTꢌꢀ4FMFDUꢀix1wꢀPOꢀUIFꢀiFreq.  
RangewꢀTXJUDIꢁꢀiBPwꢀ CBOEQBTTꢃꢀPOꢀUIFꢀiFilter  
TypewꢀTXJUDIꢀBOEꢀi12dBwꢀPSꢀi24dBwꢀPOꢀUIFꢀ  
iFilter Mode/SlopewꢀTXJUDIꢀBOEꢀBOꢀBQQSPQSJBUFꢀ  
iFilter Freq.wꢀ ꢑꢈꢋꢓꢈꢀ)[ꢀJTꢀBꢀHPPEꢀTUBSUJOHꢀQPJOUꢃꢌꢀꢀ  
5IFꢀiInfrasonic FilterwꢀBOEꢀiBass EQwꢀGFBUVSFTꢀ  
cannot be used in this mode.  
/FYUꢁꢀUVSOꢀZPVSꢀBUUFOUJPOꢀUPꢀUIFꢀiCH 3&4  
Input Sectionwꢌꢀꢀ5IFTFꢀTFUUJOHTꢀXJMMꢀEFUFSNJOFꢀ  
the high-pass cutoff and slope of the high pass  
filtering applied to the HF (high-frequency)  
channels as well as the low-pass cutoff frequency  
and slope for the MF channels’ bandpass filter.  
4FMFDUꢀix1wꢀPOꢀUIFꢀiFreq. RangewꢀTXJUDIꢀJGꢀZPVSꢀ  
desired MF to HF crossover frequency is below  
ꢇꢈꢈꢀ)[ꢌꢀ4FMFDUꢀix10wꢀPOꢀUIFꢀiFreq. RangewꢀTXJUDIꢀ  
if your desired MF to HF crossover frequency  
JTꢀBCPWFꢀꢇꢈꢈꢀ)[ꢌꢀ4FMFDUꢀiHPwꢀ IJHIꢋQBTTꢃꢀPOꢀUIFꢀ  
iFilter TypewꢀTXJUDIꢀBOEꢀi12dBwꢀPSꢀi24dBwꢀ  
POꢀUIFꢀiFilter Mode/SlopewꢀTXJUDIꢀBOEꢀBOꢀ  
BQQSPQSJBUFꢀiFilter Freq.w  
After proper adjustment of the 450/4v2’s CH  
1&2 and CH 3&4, and the subwoofer amplifier’s  
iInput RangewꢀBOEꢀiInput Sens.wꢁꢀZPVꢀDBOꢀGJOFꢀ  
tune filter frequencies and slopes and attenuate  
the LF, MF and HF channel pair or with the  
iInput Sens.wꢀDPOUSPMTꢀUPꢀBDIJFWFꢀQSPQFSꢀCBMBODFꢌ  
'PSꢀQSPQFSꢀBEKVTUNFOUꢀPGꢀUIFꢀiInput Sens.wꢀ  
controls of the 450/4v2 use the method shown in  
Appendix B (page 22). For precise filter frequency  
information for the 450/4v2 refer to Appendix  
A (page 22). Refer to the subwoofer amplifier  
owner’s manual for proper adjustments.  
Input Connections: one stereo pair of source  
unit outputs is connected to the CH 1&2  
JOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi2chwꢀPOꢀUIFꢀ  
iInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2 Input  
SectionwꢃꢀBOEꢀUIFꢀTPVSDFꢀVOJUꢊTꢀEFEJDBUFEꢀ  
subwoofer output is connected to the  
subwoofer amplifier inputs. In this mode, the  
450/4v2’s preamp output is not used.  
Result: the user has the ability to control the  
absolute level of the subwoofer channel  
relative to the MF and HF channels.  
The most common application of tri-  
Input Connections: a single pair of stereo  
source unit outputs is connected to the CH  
ꢂꢎꢅꢀJOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi2chwꢀPOꢀ  
UIFꢀiInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2  
Input Sectionwꢃꢌꢀ4VCXPPGFSꢀBNQMJGJFSꢀJOQVUTꢀ  
are connected to the preamp outputs of the  
ꢆꢇꢈꢉꢆWꢅꢀ 4FMFDUꢀi1&2wꢀPOꢀUIFꢀiSignal Fromwꢀ  
TXJUDIꢀJOꢀUIFꢀiPreamp Output Sectionwꢃꢌꢀ  
Result: the relative level of all channels will be  
GJYFEꢀCZꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢊTꢀiInput Sens.wꢀTFUUJOHTꢀ  
and will not be user adjustable from the front  
of the vehicle.  
amplification in mobile audio is to drive a  
subwoofer system from one or more amplifiers  
or channels (LF channels), mid-range speakers  
from a separate amplifier or set of channels  
(MF channels) and high-frequency speakers  
from a separate amplifier or set of channels  
(HF channels). One such configuration is to  
run subwoofers off the LF channel(s), mid-  
bass speakers off the MF channels, and a  
passively crossed over mid/high frequency  
component speaker systems on the HF channels.  
Another approach is to run subwoofers off the  
LF channel(s), mid-woofers off the MF channels  
and tweeters off the HF channels (all actively  
crossed over).  
By activating the CH 1&2 bandpass filter  
feature, the 450/4v2 can easily be configured  
to drive a tri-amplified system in conjunction  
with a separate subwoofer amplifier that  
includes a low-pass filter. CH 3&4 of the  
450/1 will drive the HF speakers (75W x 2),  
CH 1&2 will drive the MF speakers (150W  
x 2) and the separate subwoofer amp(s)  
will drive the LF speakers (subwoofers).  
IMPORTANT  
!
Set the subwoofer amplifier’s “Input  
Sens.” with the source unit’s subwoofer  
level control set at 3/4 of full output.  
Refer to the subwoofer amplifier owner’s  
manual for proper adjustment.  
B) Fade Subwoofer Level vs. MF/HF Level  
Required: a source unit or processor with front  
and rear pairs of outputs is required.  
Input Connections: one stereo pair of source  
unit outputs is connected to the CH 1&2  
JOQVUTꢀPGꢀUIFꢀꢆꢇꢈꢉꢆWꢅꢀ TFMFDUꢀi2chwꢀPOꢀUIFꢀ  
iInput ModewꢀTXJUDIꢀJOꢀUIFꢀiCH 1&2 Input  
SectionwꢃꢀBOEꢀUIFꢀTFDPOEꢀTUFSFPꢀQBJSꢀPGꢀTPVSDFꢀ  
unit outputs is connected to the subwoofer  
amplifier inputs. In this mode, the 450/4v2’s  
preamp output is not used.  
Result: the user has the ability to adjust the level  
of the subwoofer channel relative to the mid  
and high-frequency channels via the source  
unit’s fader control, without exceeding the  
maximum clean output level set by each  
BNQMJGJFSꢀTFDUJPOꢊTꢀiInput Sens.wꢀDPOUSPMTꢌ  
20 | JL Audio - 450/4v2 Owner’s Manual  
21  
 
APPENDIX A:  
APPENDIX B:  
Precise Frequency Selection Chart  
Input Sensitivity Level Setting  
3) 4XJUDIꢀUIFꢀiInput VoltagewꢀUPꢀiLowwꢀBOEꢀ  
UVSOꢀUIFꢀiInput Sens.wꢀDPOUSPMꢀPOꢀCPUIꢀTFUTꢀPGꢀ  
channels all the way down.  
4) Set the source unit volume to 3/4 of full  
volume. If either set of channels is being  
driven by a source unit’s dedicated subwoofer  
output, also adjust the source unit’s subwoofer  
level control to 3/4 of maximum output. This  
will allow for reasonable gain overlap with  
moderate clipping at full volume.  
8)ꢀ*ODSFBTFꢀUIFꢀiInput SensꢌwꢀDPOUSPMꢀVOUJMꢀ  
the target voltage is delivered for that set  
of channels. If excessive voltage is read  
on either set of channels with the control  
at minimum (full counterclockwise),  
TXJUDIꢀUIFꢀBQQSPQSJBUFꢀiInput Voltagewꢀ  
TXJUDIꢀUPꢀiHighwꢀBOEꢀSFꢋBEKVTUꢌ  
9) Once you have adjusted each set of channels to  
its maximum unclipped output level, reconnect  
UIFꢀTQFBLFS Tꢃꢌꢀ5IFꢀiInput Sens.wꢀDPOUSPMTꢀDBOꢀ  
now be adjusted downward if either or both  
sets of channels requires attenuation to achieve  
the desired system balance.  
“FILTER FREQ” CH 1&2 / CH 3&4  
APPENDIX A:  
Input Sensitivity Level Setting  
Detent  
Number  
Panel  
Marking  
Actual  
Freq.  
+-ꢀ"VEJPꢀBNQMJGJFSTꢀVUJMJ[JOHꢀUIFꢀ3FHVMBUFEꢀ  
Intelligent Power Supply (R.I.P.S.) allow  
delivery of their rated power when connected  
to any load impedance from 1.5 - 4Ω per  
channel and when connected to a charging  
system with any voltage from 11 - 14.5V. This  
design is beneficial for many reasons. One of  
these reasons is ease of setup. Because each  
JL Audio amplifier will always deliver the  
same amount of power within its operational  
range of impedances and supply voltages, the  
maximum, unclipped output is very predictable.  
This makes setting the gain structure via the  
input sensitivity controls very simple. Following  
the directions below will allow the user to adjust  
the input sensitivity of the amplifier(s) simply  
and easily in just a few minutes using equipment  
which is commonly available in installation bays.  
Full counter-clockwise: 58  
01 . . . . . . . . . . . . . . . . . . . . . . . . . . . .58  
02 . . . . . . . . . . . “50” . . . . . . . . . . . .58  
03 . . . . . . . . . . . . . . . . . . . . . . . . . . . .58  
04 . . . . . . . . . . . . . . . . . . . . . . . . . . . .58  
05 . . . . . . . . . . . . . . . . . . . . . . . . . . . .59  
06 . . . . . . . . . . . . . . . . . . . . . . . . . . . .60  
07 . . . . . . . . . . . . . . . . . . . . . . . . . . . .61  
08 . . . . . . . . . . . “60” . . . . . . . . . . . .63  
09 . . . . . . . . . . . . . . . . . . . . . . . . . . . .65  
10 . . . . . . . . . . . . . . . . . . . . . . . . . . . .67  
11 . . . . . . . . . . . . . . . . . . . . . . . . . . . .69  
12 . . . . . . . . . . . . . . . . . . . . . . . . . . . .71  
13 . . . . . . . . . . . . . . . . . . . . . . . . . . . .74  
14 . . . . . . . . . . . “75” . . . . . . . . . . . .77  
15 . . . . . . . . . . . . . . . . . . . . . . . . . . . .80  
16 . . . . . . . . . . . . . . . . . . . . . . . . . . . .82  
17 . . . . . . . . . . . . . . . . . . . . . . . . . . . .85  
18 . . . . . . . . . . . . . . . . . . . . . . . . . . . .90  
19 . . . . . . . . . . . . . . . . . . . . . . . . . . . .93  
20 . . . . . . . . . . . “95” . . . . . . . . . . . .97  
21 . . . . . . . . . . . . . . . . . . . . . . . . . . . 102  
22 . . . . . . . . . . . . . . . . . . . . . . . . . . . 107  
23 . . . . . . . . . . . . . . . . . . . . . . . . . . . 113  
24 . . . . . . . . . . . . . . . . . . . . . . . . . . . 120  
25 . . . . . . . . . . . . . . . . . . . . . . . . . . . 127  
26 . . . . . . . . . . “130” . . . . . . . . . . 135  
27 . . . . . . . . . . . . . . . . . . . . . . . . . . . 143  
28 . . . . . . . . . . . . . . . . . . . . . . . . . . . 153  
29 . . . . . . . . . . . . . . . . . . . . . . . . . . . 171  
30 . . . . . . . . . . . . . . . . . . . . . . . . . . . 182  
31 . . . . . . . . . . . . . . . . . . . . . . . . . . . 201  
32 . . . . . . . . . . “200” . . . . . . . . . . 223  
33 . . . . . . . . . . . . . . . . . . . . . . . . . . . 253  
34 . . . . . . . . . . . . . . . . . . . . . . . . . . . 289  
35 . . . . . . . . . . . . . . . . . . . . . . . . . . . 337  
36 . . . . . . . . . . . . . . . . . . . . . . . . . . . 404  
37 . . . . . . . . . . . . . . . . . . . . . . . . . . . 474  
38 . . . . . . . . . . “500” . . . . . . . . . . 514  
Full-clockwise: 542  
5) Using the chart below, determine the  
target voltage for input sensitivity  
adjustment according to the nominal  
impedance of the speaker system  
connected to each set of outputs.  
IMPORTANT  
!
6) Verify that you have disconnected the speakers  
before proceeding. Play a track with an  
appropriate sine wave (within the frequency  
range to be amplified by each set of channels)  
at 3/4 source unit volume.  
7)$POOFDUꢀUIFꢀ"$ꢀWPMUNFUFSꢀUPꢀUIFꢀiCH 1&2  
Speaker OutputswꢀPSꢀiCH 3&4 Speaker  
OutputswꢀDPOOFDUPSTꢀPGꢀUIFꢀBNQMJGJFSꢌꢀ*GꢀUIFꢀ  
channel pair is operating in stereo, it is only  
necessary to measure one channel. If bridged,  
make sure you test the voltage at the correct  
connectors (L+ and R–).  
Do not increase any “Input Sens.” setting in  
the system beyond the maximum level  
established during this procedure. Doing so  
will result in audible distortion and possible  
speaker damage.  
*UꢀXJMMꢀCFꢀOFDFTTBSZꢀUPꢀSFꢋBEKVTUꢀUIFꢀiInput  
Sens.wꢀGPSꢀUIFꢀBGGFDUFEꢀDIBOOFMTꢀJGꢀBOZꢀFRVBMJ[FSꢀ  
CPPTUꢀJTꢀBDUJWBUFEꢀBGUFSꢀTFUUJOHꢀUIFꢀiInput  
Sens.wꢀXJUIꢀUIJTꢀQSPDFEVSFꢌꢀ5IJTꢀBQQMJFTꢀUPꢀ  
any EQ boost circuit, including the amplifier’s  
iBass EQwꢀBOEꢀTPVSDFꢀVOJUꢀUPOFꢀDPOUSPMTꢀPSꢀ&2ꢀ  
circuits. EQ cuts will not require re-adjustment.  
Necessary Equipment  
tꢀ%JHJUBMꢀ"$ꢀ7PMUNFUFS  
tꢀ$%ꢀXJUIꢀBꢀTJOFꢋXBWFꢀUFTUꢀUPOFꢀSFDPSEFEꢀBUꢀ  
0 dB reference level in the frequency range  
to be amplified for that set of channels  
ꢇꢈꢀ)[ꢀGPSꢀTVCXPPGFSꢀDIBOOFMTꢁꢀꢂꢀL)[ꢀGPSꢀ  
a midrange application). The CleanSweep®  
$BMJCSBUJPOꢀ%JTDꢀDPOUBJOTꢀUIFꢀBQQSPQSJBUFꢀ  
test tones and is available for sale at  
http://store.jlaudio.comꢀ%PꢀOPUꢀVTFꢀBUUFOVBUFEꢀ  
test tones (-10 dB, -20 dB, etc.).  
CHANNELS 1&2  
Nom.  
CHANNELS 3&4  
Impedance  
Stereo  
24.5 V  
24.5 V  
24.5 V  
21.2 V  
17.3 V  
15.0 V  
Bridged  
Stereo  
17.3 V  
17.3 V  
17.3 V  
15.0 V  
12.2 V  
10.6 V  
Bridged  
34.6 V  
The Nine-Step Procedure  
8Ω  
6Ω  
49.0 V  
42.4 V  
(follow this procedure for each pair of channels)  
1) %JTDPOOFDUꢀUIFꢀTQFBLFS TꢃꢀGSPNꢀUIFꢀ  
BNQMJGJFSꢊTꢀiFront Speaker OutputswꢀBOEꢀ  
iRear Speaker OutputswꢀDPOOFDUPSTꢌ  
2) Turn off all processing on the source  
unit (bass/treble, loudness, EQ, etc.).  
Set fader control to center position  
30.0 V  
4Ω  
34.6 V  
24.5 V  
3Ω  
30.0 V  
21.2 V  
not recommended  
not recommended  
not recommended  
not recommended  
2Ω  
and subwoofer level control to 3/4 of  
maximum (if used to drive the 450/4v2).  
1.5Ω  
22 | JL Audio - 450/4v2 Owner’s Manual  
23  
 
APPENDIX C: TROUBLE SHOOTING  
“How do I properly set the input sensitivity on my amplifier”  
“My amplifier shuts off once in a while, usually at higher volumes”  
Check your voltage source and grounding point. The power supply  
Please refer to Appendix B (page 22) to set the input sensitivity for  
maximum, low-distortion output.  
of the 450/4v2 will operate with charging system voltages  
down to 10V. Shutdown problems at higher volume levels  
can occur when the charging system voltage drops below  
10V. These dips can be of very short duration making them  
FYUSFNFMZꢀEJGGJDVMUꢀUPꢀEFUFDUꢀXJUIꢀBꢀDPNNPOꢀ%$ꢀWPMUNFUFSꢌꢀ  
To ensure proper voltage, inspect all wiring and termination  
points. It may also be necessary to upgrade the ground  
wire connecting the battery to the vehicle’s chassis and the  
power wire connecting the alternator to the battery. Many  
vehicles employ small (10 AWG - 6 AWG) wire to ground the  
battery to the vehicle’s chassis and to connect the alternator to  
the battery. To prevent voltage drops, these wires should be  
upgraded to 4 AWG when installing amplifier systems with  
main fuse ratings above 60A. Grounding problems are the  
leading cause of misdiagnosed amplifier “failures.”  
“My amplifier doesn’t turn on”  
Check the fuse, not just visually, but with a continuity meter. It is  
possible for a fuse to have poor internal connections that  
cannot be found by visual inspection. It is best to take the  
fuse out of the holder for testing. If no problem is found with  
the fuse, inspect the fuse-holder.  
Check the integrity of the connections made to each of the  
i+12VDCwꢁꢀꢀiGroundwꢁꢀꢀBOEꢀiRemotewꢀUFSNJOBMT. Ensure  
that no wire insulation is pinched by the terminal set screw  
and that each connection is tight.  
Check to make sure there is +12V at the “Remote” connection of the  
amplifier. In some cases, the turn-on lead from the source unit  
is insufficient to turn on multiple devices and the use of a relay  
is required. To test for this problem, jump the i+12VDCw wire  
to the iRemotew terminal to see if the amplifier turns on.  
“My amplifier turns on, but there is no output”  
“I get a distorted / attenuated sound coming out of the speaker(s)”  
Check the speaker wires for a possible short, either between the  
Check the input signal using an AC voltmeter to measure the  
voltage from the source unit while an appropriate test tone is  
played through the source unit (disconnect the input cables  
from the amplifier prior to this test). The frequency used  
should be in the range that is to be amplified by the amplifier  
FYBNQMFꢍꢀꢇꢈꢀ)[ꢀGPSꢀBꢀTVCꢀCBTTꢀBQQMJDBUJPOꢀPSꢀꢂꢀL)[ꢀGPSꢀBꢀGVMMꢀ  
range / high-pass application). A steady, sufficient voltage  
(between 200mV and 8.0-volts) should be present at the  
output of the signal cables.  
Check the output of the amplifier. Using the procedure explained in  
the previous check item (after plugging the input cables back  
into the amplifier) test for output at the speaker outputs of  
the amplifier. Unless you enjoy test tones at high levels, it is  
a good idea to remove the speaker wires from the amplifier  
while doing this. Turn the volume up approximately half  
way. 5V or more should be measured at the speaker outputs.  
This output level can vary greatly between amplifiers but it  
should not be in the millivolt range with the source unit at  
half volume. If you are reading sufficient voltage, check your  
speaker connections as explained below.  
positive and negative leads or between either speaker lead  
and the vehicle’s chassis ground. If a short is present, you  
will experience distorted and/or attenuated output. The  
iLow Ωw light will illuminate in this situation. It may be  
helpful to disconnect the speaker wires from the amplifier  
and use a different set of wires connected to a test speaker.  
Check the nominal load impedance to verify that each channel  
of the amplifier is driving a load equal to or greater than  
1.5 ohms in stereo mode (3 ohms bridged).  
Check the input signal and input signal cables to make sure signal  
is present at the Amplifier Inputs” and the cables are not  
pinched or loose. It may be helpful to try a different set of  
cables and/or a different signal source to be sure.  
“My amplifier’s output fluctuates when I tap on it or hit a bump”  
Check the connections to the amplifier. Make sure that the  
insulation for all wires has been stripped back far enough to  
allow a good contact area inside the terminal block.  
Check the input connectors to ensure that they all are making good  
contact with the input jacks on the amplifier.  
Check to ensure that the speaker wires are making a good  
connection with the metal inside the terminal block. The  
speaker wire connectors are designed to accept up to 8 AWG  
wire. Make sure to strip the wire to allow for a sufficient  
connection with the metal inside the terminal block.  
24 | JL Audio - 450/4v2 Owner’s Manual  
25  
 
APPENDIX D:  
450/4v2 Specifications  
General Specifications:  
Channels 3 & 4:  
Recommended Fuse Value: 60A  
Amplifier Topology: Class A/B with patented Absolute  
Symmetry™ dual N-Channel MOSFET output design  
Power Supply: Independent, pulse width modulation-  
regulated switching power supply with multistage  
impedance optimizing circuitry.  
Recommended Fuse Type: AFS, AGU or MaxiFuse™  
Input Sections:  
No. of Inputs: Two Stereo Pairs (CH 1&2, CH 3&4)  
Input Type: Differential-balanced with RCA jack inputs  
Input Range: Switchable from 200mV - 2V RMS  
to 800mV - 8V RMS  
Rated Power (Stereo):  
75W RMS x 2 @ 1.5 - 4Ω (11V - 14.5V)  
Rated Power (Bridged):  
150W RMS x 1 @ 3 - 8Ω (11V - 14.5V)  
Channels 1 & 2:  
THD at Rated Power: <0.03% @ 4Ω per channel  
(20 Hz - 20 kHz)  
Amplifier Topology: Class A/B with patented Absolute  
Symmetry™ dual N-Channel MOSFET output design  
Power Supply: Independent, pulse width modulation-  
regulated switching power supply with multistage  
impedance optimizing circuitry.  
Signal to Noise Ratio: >108.5 dB referred to rated power  
(A-weighted, 20 Hz - 20 kHz noise bandwidth)  
Frequency Response: 5 Hz - 30 kHz (+0, -1 dB)  
Damping Factor: >200 @ 4Ω per ch. / 50 Hz, >100 @ 2Ω  
per ch. / 50 Hz  
Rated Power (Stereo):  
150W RMS x 2 @ 1.5-4Ω (11V - 14.5V)  
Slew Rate: 25V/μs  
Rated Power (Bridged):  
Channel 3&4 Filter: State-variable, 12 dB/octave  
Butterworth or 24 dB/octave Linkwitz-Riley High-Pass  
with continuously variable cutoff frequency from 50 - 500  
Hz, switchable to a range of 500 - 5000 Hz, via x10 switch.  
300W RMS x 1 @ 3-8Ω (11V - 14.5V)  
THD at Rated Power: <0.03% @ 4Ω per channel  
(20 Hz-20 kHz)  
Signal to Noise Ratio: >108.5 dB referred to rated power  
(A-weighted, 20 Hz-20 kHz noise bandwidth)  
Frequency Response: 5 Hz - 30 kHz (+0, -1dB)  
Damping Factor: >200 @ 4Ω per ch. / 50 Hz, >100 @ 2Ω  
per ch. / 50 Hz  
Preamp Output:  
2-Channel pass-through type, switch-selectable to pass  
signal from CH 1&2 inputs only, from CH 3&4 inputs only  
or from all four inputs (summed).  
Slew Rate: 25V/μs  
CH 1&2 Filter: State-variable, 12 dB/octave Butterworth or  
24 dB/octave Linkwitz-Riley Low-Pass or High-Pass with  
continuously variable cutoff frequency from 50 - 500 Hz,  
switchable to a range of 500 - 5000 Hz, via x10 switch.  
Can also be cascaded from Channel 3&4 filter’s cutoff  
frequency to operate as a bandpass filter for tri-amp  
configurations. Defeatable.  
Dimensions (LxWxH):  
19.70 in. x 9.25 in. x 2.36 in. (500 mm x 235 mm x 60 mm)  
LF Boost: Single-band, fixed-frequency (48 Hz), fixed “Q”  
+6 dB boost. Defeatable. Port for optional remote bass  
control to provide variable boost control from 0 to +15 dB.  
Infrasonic Filter: 24 dB/octave @ 30 Hz, defeatable.  
Due to ongoing product development, all specifications are subject to  
change without notice.  
26 | JL Audio - 450/4v2 Owner’s Manual  
27  
 
INSTALLATION NOTES:  
Use this diagram to document your amplifier’s switch and control positions.  
+12VDC Ground Remote  
Preamp Output Section  
CH 1 & 2 Speaker Outputs  
CH 1 & 2 Bass Control  
CH 1 & 2 Filter Section  
CH 1 & 2 Input Section  
CH 3 & 4 Filter Section  
CH 3 & 4 Input Section  
CH 3 & 4 Speaker Outputs  
|
Signal From  
Bass EQ  
Infrasonic Filter  
Freq. Range Filter Mode Slope  
Input Voltage Input Sens.  
Freq. Range High-Pass Filter  
Input Voltage Input Sens.  
|
|
|
|
|
|
|
|
|
|
|
|
1 & 2 3 & 4 All  
Off On  
Off 30Hz  
x1 x10 Off 12dB 24dB  
Low High  
x1 x10 Off 12dB 24dB  
Low High  
95  
95  
Either  
feature  
Filter Type  
Input Mode  
Also sets  
low-pass  
cutoff for  
CH 1 & 2  
Bandpass  
Filter  
75  
60  
50  
Filter Freq. (Hz)  
130  
75  
60  
50  
HP Filter Freq. (Hz)  
130  
200  
500  
sums the  
CH 1&2 input  
signals to  
mono when  
activated.  
200  
450/4v2  
Left  
150W  
Right  
150W  
Left  
75W  
Right  
75W  
Four-Channel System Amplifier  
|
|
|
(1.5-4Ω)  
500  
LP BP HP  
2ch 4ch  
(1.5-4Ω)  
(if selected)  
1 & 2  
1 & 2  
and  
Remote  
Bass Port  
CH 1  
(Left)  
CH 2  
(Right)  
CH 3  
(Left)  
CH 4  
(Right)  
Inputs  
Only  
Left Output Right Output  
Bridged: 300W x 1 (3-8Ω)  
Bridged: 150W x 1 (3-8Ω)  
3 & 4  
28 | JL Audio - 450/4v2 Owner’s Manual  
29  
 
NOTES  
NOTES  
30 | JL Audio - 450/4v2 Owner’s Manual  
31  
 

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