Audio Design JX360-4 User Manual

OWNER’S MANUAL

360W 4-Channel, Full-Range 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, 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 our Technical Support Department

at [phone] during business hours.

IMPORTANT

!

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.).

Chassis Ground

Connector

(pg. 5)

Power Status

Indicator

(pg. 11)

+12 V Power

Connector

(pg. 5)

+12 VDC Ground Remote

Protection Status

Indicator

(pg. 11)

Remote Turn-On

Input Mode

Selector

(pg. 7)

Connector

(pg. 6)

High-Level

Input Jack

(pg. 6,7)

CH 1 & CH 2

Preamp

Input Jacks

(pg. 6)

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:

CH 1 & CH 2

Speaker Outputs

(pg. 10)

CH. 1

(L)

CH 3 & CH 4

Preamp Input Jacks

(pg. 6)

Left & Right

Preamp Output Jacks

CH. 2

(R)

(pg. 9)

High-Level

Input Jack

(pg. 6,7)

CH 3 & CH 4

Speaker Outputs

(pg. 10)

BridgedBridged

CH. 3

(L)

CH. 4

(R)

INSTALLATION APPLICATIONS

This amplifier is designed for operation in
vehicles with 12 volt, 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 w arra nty.

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.

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:

The outer shell of your JL Audio amplifier is
designed to remove heat from the amplifier
circuitry. For optimum cooling performance, this
outer shell 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.

Mounting the amplifier upside down is
strongly discouraged.

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.

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 so that it does not
come loose in the event of a collision or a sudden
jolt to the vehicle.

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.

ENGLISH

Filter Mode

Selector

(pg. 8)

Filter

Frequency

Control

(pg. 8)

Sensitivity

Control

(pg. 8)

Filter Mode

Selector

(pg. 8)

Frequency

Filter

Control

(pg. 8)

Input

Sensitivity

Control

(pg. 8)

Input

2 JL Audio JX360/4 3

Remote

CH. 3

(L)

CH. 4

(R)

CH. 1

(L)

CH. 2

(R)

BridgedBridged

IMPORTANT

!

PRODUCT DESCRIPTION

The JL Audio JX360/4 is a four-channel,
full-range audio amplifier utilizing Class A/B
technology for all channels.

The JX360/4 can be operated with a wide
variety of source units and system configurations.
For detailed specifications, please refer to
Appendix B (page 13).

TYPICAL INSTALLATION SEQUENCE

The following represents the sequence
for a typical amplifier installation, using an
aftermarket source unit or OEM Interface
product. Additional steps and different
procedures may be required in some applications.
If you have any questions, please contact your
authorized JL Audio dealer for assistance.

1) Disconnect the negative battery post

connection and secure the disconnected cable
to prevent accidental re-connection during
installation. This step is not optional.

2) Run 4 AWG power wire 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 larger
power wire and a power distribution block if
additional amplifiers are being installed with
the JX360/4.

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.
Do not install the fuse until the power wire
has been securely connected to the amplifier.

4) Run signal cables and remote turn-on wire

from the source unit to the final amplifier
mounting location.

5) Run speaker cables 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 the same size power wire as the
wire connected to the “+12VDC” connection
(minimum 4 AWG), 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 5 for important notice).

7)

Securely mount the amplifier using
appropriate hardware.

8) Connect the positive and negative power
wires to the amplifier.

9) Connect the remote turn-on wire
to the amplifier.

10) Connect the input cables to the amplifier.

11) Connect the speaker cables 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 the power wire fuse (50A for a
single JX360/4) 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 A (page 12)
for the recommended input sensitivity
setting method.

16) Enjoy the fruits of your labor with your
favorite music.

POWER CONNECTIONS

Before installing the amplifier, 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.

+12 VDC Ground

The JX360/4’s “+12VDC ” and “Ground”
connections are designed to accept 4 AWG power
wire. 4 AWG is a minimum power wire size for

this amplifier.

If you are installing the JX360/4 with other
amplifiers and wish to use a single main power
wire, use 2 AWG or larger main power wire
(depending on the overall current demands of all
the amplifiers in the system). This 2 AWG or
larger power wire should terminate into a fused
distribution block mounted as close to the
amplifiers as possible and should connect to the
JX360/4 with 4 AWG power wire.

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.).

To connect the power and ground wires
to the amplifier, strip 1/2-inch (12 mm) of
insulation from each wire and insert the bare
wire into the the appropriate terminal block
positions on the JX360/4. Use the supplied

2.5 mm hex wrench to secure the wire via
the screw on the top of each terminal.

The “GROUND” connection should be made
using 4 AWG wire 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. The use of a #10 sheet metal screw
and star washer to lock down the connection is
advisable. Alternatively, you can use a specialized
grounding lug, such as the JL Audio XB-MGLU.

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.

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 batter y. To prevent
voltage drops, these wires should be upgraded
to 4 AWG when installing amplifier systems
with main fuse ratings above 60A.

FUSE REQUIREMENTS

An appropriate fuse at the main power wire(s)
to the amplifier(s) is vital for vehicle safety! This
fuse must be installed within 18 inches (45 cm)
of the positive battery post connection. If the
JX360/4 is the only device connected to this main
wire, use a 50A AGU or MAXI® fuse (no other
fuse is required in this situation).

When running multiple devices from one
main power wire, the main fuse value and rating
of the main power wire must be high enough
for all of the equipment being run from it. Use a
fused distribution block to split the main power
wire feed to each device, with appropriate fusing
and power wire for each device.

ENGLISH

4 JL Audio JX360/4 5

IMPORTANT

!

IMPORTANT

!

TURNON LEAD

CH. 3

(L)

CH. 4

(R)

CH. 1

(L)

CH. 2

(R)

BridgedBridged

The JX360/4 is turned on and off

using a conventional +12V remote turn-

on lead, typically controlled by the
source unit’s remote turn-on output.

+12 VDC Ground Remote

The amplifier will turn on when +12V is

present at its “Remote” 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 ignition­switched circuit.

18 AWG wire is more than adequate for the
remote turn-on connection. To connect the
remote turn-on wire to the amplifier, strip 1/2­inch (12 mm) of insulation from the wire and
insert it into the “Remote” receptacle on the
power connector. Tighten the connector down
using the supplied 2.5 mm hex wrench.

INPUT SECTIONS

The JX360/4’s has two input sections: one for
Channels 1&2 and another for Channels 3&4.
These input sections allows you to send signals to
the amplifier sections through the use of either
two or four inputs. Each input section offers
two input connection methods, one for high­level (speaker level) signals and one for low-level
(preamp level) signals.

1) Low-Level Inputs: A standard left/

right pair of RCA type jacks in the
“Low-Level Inputs” section is used for
preamp level (low-level) signal input
on the JX360/4. This is the preferred
connection method whenever available.

2) Hi-Level Inputs: If your system does not offer

a preamp level signal option, you can connect
speaker level signals directly to the “Hi-Level
Inputs” connectors using the supplied mating
connectors and wire harnesses. Simply splice
the appropriate left/right and positive/negative
wires to the included harnesses and plug the
harness into the “Hi-Level Inputs” connectors
on the amplifier. The JX360/4 will attenuate
the high-level signals to make them compatible
with its input stages.

Make sure you observe correct polarity in
making the “Hi-Level Input” connections.
Failure to do so will reduce bass and affect
stereo imaging.

The connections for the “Hi-Level Inputs” plug wires
are as follows from left to right on the plug:

Channels 1&2 (FRONT)

White: Left Positive (+)

White/Black: Left Negative (–)
Black: Common Ground (rarely used)*

Gray: Right Positive (+)

Gray/Black: Right Negative (–)

Channels 3&4 (REAR or SUB)

Green: Left Positive (+)

Green/Black: Left Negative (–)
Black: Common Ground (rarely used)*

Purple: Right Positive (+)
Purple/Black: Right Negative (–)

*The only time you will use the Common Ground
connections is with some older (pre-1980’s) factory
systems or head units that ground their speakers to
chassis ground. To use these connections, ground
the black wires on the plugs to chassis ground and

only connect the Left and Right Positive plug wires

to the factory radio outputs.

“Input Mode” Switch

If you wish to send four discrete channels of
input into the JX360/4, simply use all four inputs
(Channels 1 & 2 and Channels 3 & 4) and set the
“Input Mode” switch to “4 Ch.”.

If you wish to feed all four channels by using
only two channels of input, set the “Input Mode”
switch to “2 Ch.” and use only the inputs to
Channels 1 & 2.

When Bridging the Amplifier:

If you are bridging the amplifier down
to two channels in a stereo application,
you must set the "Input Mode" switch to
the "4 Ch." position and feed the input of
each bridged channel pair individually.

For mono applications (where both bridged
channel pairs will reproduce the same signal), you
can select the "2 Ch." position and only feed the
Ch. 1 & 2 Inputs.

Any bridged channel pair must be fed by both
Input Channels corresponding to it (Left and
Right). Failure to do so will result in significant
audible distortion.

See "Bridging Considerations" section on Page

10 for further information.

ENGLISH

6 JL Audio JX360/4 7

INPUT SENSITIVITY CONTROLS

IMPORTANT

!

The controls labeled “Input Sens.” located in
each channel pair's control section 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.)

FILTER CONTROLS

The active filter built into each channel
section of the JX360/4 can be used to eliminate
potentially harmful and/or undesired frequencies
from making their way through the amplifier
sections to the speaker(s). This serves to improve
tonal balance and to avoid distortion and possible
speaker failure. Correct use of these filters can
substantially increase the longevity and fidelity
of your audio system.

“LP ” (Low-Pas s): Configures the filter to
attenuate frequencies above the selected filter
frequency at a rate of 12dB per octave. This is
useful for connection of subwoofer(s) to one
or both of the JX360/4’s channel pairs in a
bi-amplified system.

2) “Filter Freq. (Hz)” A simple rotary control
in each channel section adjusts the filter
cutoff frequency of the filter type you have
selected with the “Filter Mode” switch. This
control will have no effect if you have selected
the “Off” position for the “Filter Mode”).

Each filter in the JX360/4 is fully variable
between 50 Hz and 200 Hz. The "80"
Hz position is a good starting point for
tuning systems utilizing typical subwoofers
and component or coaxial speakers.

PREOUTS

The JX360/4 incorporates a pass-through

preamp output (Preouts) section, so that

additional amplifiers can be easily added to
the system. This pass-through pre-amp output
delivers a summed stereo signal, combining the

Ch 1 and 3 signals into a Left Preamp Output

Signal and the Ch. 2 and 4 signals into a Right

Channel Preamp Output signal. Only signals

applied to the Low-Level inputs are passed

through the Preouts. Input signals applied to

the High-Level inputs will not pass through the

Preouts.

ENGLISH

To properly set the amplifier for maximum

clean output, please refer to Appendix A (page

12) in this manual. After using this procedure,
you can then adjust any or all “Input Sens.”
levels downward if this is required to achieve the
desired system balance.

Do not increase any “Input Sens.” setting for
any channel(s) of any amplifier in the system
beyond the maximum level established during
the procedure outlined in Appendix A (page

12). Doing so will result in audible distortion
and possible speaker damage.

8 JL Audio JX360/4 9

1) “Filter Mode” Control: The JX360/4 employs a
12dB per octave filter for each pair of channels
(one filter for channels 1&2 and another filter
for channels 3&4). Each of these filters can
be configured independently into one of two
filter types or defeated completely by way of the
three-position “Filter Mode” switches:

“HP” (High-Pass): Configures the filter to
attenuate frequencies below the selected filter
frequency at a rate of 12dB per octave. This is
useful for connection of component speakers
to one or both of the JX360/4’s channel pairs in
a bi-amplified system.

Of f”: Defeats the filter completely, allowing
the full range of frequencies present at the
inputs to feed the amplifier. This is useful
for systems utilizing outboard crossovers or
requiring full-range reproduction from one or
both of the JX360/4’s channel pairs.

The preamp output signal is not affected by
any crossover filter selected (if the input signal is
full-range, the preamp output will be full-range).

Note: The signal level of the “Preouts” is always
line-level (low voltage).

SPEAKER OUTPUTS

CH. 3

(L)

CH. 4

(R)

Bridged

IMPORTANT

!

IMPORTANT

!

IMPORTANT

!

The JX360/4’s speaker outputs are designed to

accept 16 AWG - 8 AWG wire.

Each pair of the JX360/4’s channels are
designed to deliver power into speaker loads equal
to or greater than 2 ohms per channel when using
a “stereo” configuration and speaker loads equal
to or greater than 4 ohms per bridged pair of
channels when using a “bridged” configuration.

Bridged

CH. 1

(L)

CH. 2

(R)

Speaker loads below 2 ohms nominal per
channel are not recommended and will cause
the amplifier to enter a protection mode.

BRIDGING CONSIDERATIONS

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 JX360/4 has been designed
for bridging of its channel pairs without the need
for input inversion adaptors.

To bridge a pair of channels, use the
“Left +” and “Right –” speaker connectors only
(the “ Left –” and “Right +” remain unused).
When bridged, each channel will deliver
optimum power into a 4 ohm load.

When a pair of JX360/4 channels are bridged,
they will deliver 180W x 1 into a 4 ohm load or
140W x 1 into an 8 ohm load. Operating a
pair of bridged channels into a load lower
than 4 ohms is not recommended and will
cause the amplifier to enter a protection mode.

Any bridged channel pair must be fed by both
Input Channels corresponding to it (Left and
Right). Failure to do so will result in significant
audible distortion.

When a pair of the JX360/4’s channels are
operating in bridged mode, the output will be in
mono (only one channel). This mono channel
can contain right channel only information,
left channel only information or the sum of
the information from both the right and left
channels. In order to achieve one of these options,
configure the inputs to that pair of channels in
one of these two ways:

1) Left Channel Only or Right Channel Only

Information: If you wish to send a left-only

or right-only signal to a pair of the JX360/4’s
channels, use a “Y-Adaptor” to split the single
channel signal into both left and right RCA
inputs. This option is useful when using a
pair of the JX360/4’s channels to drive left
channel speakers only and the other pair of
the JX360/4’s channels to drive right channel
speakers only.

2) Left + Right Channel Information:

When bridged and fed by a stereo input, a pair
of the JX360/4’s channels will automatically
combine the left and right channels into a

summed mono (left + right) channel. This

option is useful when using a pair of the
JX360/4’s channels to drive a subwoofer system
or a summed mono center channel.

AMPLIFIER STATUS INDICATOR LIGHTS &
PROTECTION CIRCUITRY

There are two status indicator lights on the

control panel of the amplifier.

1) “Power” (Green): lights to indicate that the
amplifier is turned on and operating normally.
Located at the far left of the control panel.

2) “Protect” (Red): Indicates that the amplifier
protection circuitry has been activated
to prevent product failure due to thermal
overload, short-circuit or a dangerously
low impedance connected to the amplifier
outputs. Connecting the speaker outputs
to an impedance lower than 2 ohms stereo
(4 ohms bridged) will cause this protection
mode to activate. When this protection mode
is activated, the amplifier will shut down to
protect its circuitry. When the problem is
corrected, the amplifier will return to normal
operation and the “Protect” LED will shut off.

SERVICING YOUR AMPLIFIER

If your amplifier fails or malfunctions, please
return it to your authorized JL Audio dealer so
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
trained service personnel. Do not attempt
to service the amplifier yourself or through
unauthorized repair facilities. This will not only
void the warranty, but may result in the creation
of more problems within the amplifier.

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.

JL Audio Technical Support:

[phone]

9:00 AM – 5:30 PM (Eastern Time Zone)

Monday - Friday

ENGLISH

10 JL Audio JX360/4 11