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.

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:

Chassis Ground

Connector

(pg. 5)

+12 V Power

Remote Turn-On

CH 1 & CH 2

CH 3 & CH 4

Speaker Outputs

Speaker Outputs

Connector

Connector

(pg. 10)

(pg. 10)

(pg. 5)

(pg. 6)

+12 VDC	Ground	Remote	Bridged		Bridged
		CH. 1	CH. 2	CH. 3	CH. 4
		(L)	(R)	(L)	(R)

			CH 3 & CH 4
Power Status	Input Mode		Preamp Input Jacks		High-Level
Indicator	Selector		CH 1 & CH 2	(pg. 6)	Input Jack
(pg. 11)	(pg. 7)	High-Level		Left & Right	(pg. 6,7)
Protection Status			Preamp
Indicator		Input Jack	Input Jacks	Preamp Output Jacks
(pg. 11)		(pg. 6,7)	(pg. 6)	(pg. 9)

Filter Mode

Filter

Input

Filter Mode

Filter

Input

Selector

Frequency Sensitivity

Selector

Frequency Sensitivity

(pg. 8)

Control

Control

(pg. 8)

Control

Control

(pg. 8)

(pg. 8)

(pg. 8)

(pg. 8)

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 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.

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.

! IMPORTANT

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.

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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

Remo

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.

! 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.

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.

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Turn-On Lead

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 1/2- inch (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.

! IMPORTANT

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.

! IMPORTANT

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.

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Input Sensitivity Controls

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-Pass): 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.

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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.

! IMPORTANT

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.

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.

Off”: 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).

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Speaker OUTPUTS

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	CH. 2
(L)	(R)

! IMPORTANT

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.

! IMPORTANT

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.

! IMPORTANT

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	ENGLISH
	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

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