CH 1&2
Filter Slope
Selection / Defeat
(pg. 7)
Infrasonic Filter
On/Off Switch
(pg. 9)
Jack for
Remote Bass
Control Knob
(pg. 9)
CH 3&4
Input Voltage
Range Selector
(pg. 6)
Selects
2ch / 4ch
Input Mode
(pg. 6)
CH 3&4
HP Filter Slope
Selection / Defeat
(pg. 8)
CH 3&4
Filter Frequency
Range Selector
(pg. 8)
Selects CH 3&4
High-Pass Cutoff
Frequency and Low-Pass
Cutoff for CH 1&2
Bandpass Filter
(pg. 8)
CH 3&4
Input Sensitivity
Control
(pg. 6)
CH 1&2
Left and Right
Input Jacks
(pg. 6)
CH 3&4
Left and Right
Input Jacks
(pg. 6)
Bass EQ
On/Off Switch
(pg. 9)
CH 1&2
Filter Frequency
Range Selector
(pg. 7)
CH 1&2
Input Voltage
Range Selector
(pg. 6)
CH 1&2 Input
Sensitivity Control
(pg. 6)
CH 3&4
Speaker Outputs
(pg. 10)
Selects CH 1&2
HP or LP Cutoff
Frequency or HP Cutoff
of Bandpass Filter
(pg. 8)
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.
Cooling Efficiency Considerations:
Your JL Audio amplifier employs an 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:
• Amplifier mounted vertically with heat sink fins
pointing up: Optimum
• Amplifier mounted horizontally,
right side up: Good
• Amplifier mounted horizontally, but upside down:
Fair (not recommended if there is less than 1 inch
(2.5 cm) clearance above the amplifier heat sinks)
• Amplifier mounted vertically with heat sink fins
pointing laterally: Fair
• Amplifier mounted vertically with heat sink fins
pointing down: Poor (not recommended)
If mounting the amplifier under a seat, make sure
there is at least 1 inch (2.5 cm) of space above the
amplifier heat sink fins to permit proper cooling.
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 the supplied
screws so that it does not come loose in the event
of a collision or a sudden jolt to the vehicle (20 lbs.
of aluminum traveling at 60 MPH will hurt you).
Stupid Mistakes to Avoid:
• Check before drilling any holes in your vehicle to
make sure that you will not be drilling through a
gas tank, brake line, wiring harness or other vital
vehicle system.
• Do not run system wiring outside or underneath
the vehicle.This is an extremely dangerous
practice which can result in severe damage to
your vehicle and person.
• Protect all system wires from sharp metal
edges and wear by carefully routing them,
tying them down and using grommets and
loom where appropriate.
• Do not mount the amplifier in the engine
compartment, under the vehicle, on the roof
or in any other area that will expose the amplifier
circuitry to the elements.
JL AUDIO
450/4
3
Preamp Output
Signal Selector
(pg. 9)
Left and Right
Preamp Output Jacks
(pg. 9)
Remote Turn-On
Connector
(pg. 6)
Chassis Ground
Connector
(pg. 5)
+12 V Power
Connector
(pg. 5)
CH 1&2
Speaker Outputs
(pg. 10)
PROTECT YOUR HEARING!
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.
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.).
SERIAL NUMBER
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.
Serial Number:
_______________________________
INSTALLATION APPLICATIONS
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.
Do not attempt to “bridge” the outputs of this
amplifier with the outputs of a second amplifier,
including an identical one.
2
JL AUDIO
450/4
