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		 A4300   
					four-channel full-range amplifier   
					OWNER’S MANUAL   
					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.   
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				PROTECT YOUR HEARING!   
					INSTALLATION APPLICATIONS   
					PLANNING YOUR INSTALLATION   
					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 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.   
					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.   
					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.   
					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.   
					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.   
					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.   
					Stupid Mistakes to Avoid   
					Chassis Ground   
					Connector   
					(pg. 5)   
					• 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.   
					Channels 1 & 2   
					Speaker Outputs   
					(pg. 8)   
					Channels 3 & 4   
					Speaker Outputs   
					(pg. 8)   
					+12 V Power   
					Connector   
					(pg. 4)   
					Remote Turn-On   
					Connector   
					(pg. 5)   
					• 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.   
					Serial Number:   
					• Protect all system wires from sharp metal   
					edges and wear by carefully routing them,   
					tying them down and using grommets and   
					loom where appropriate.   
					Power   
					Ch. 1 & 2 Filter   
					Ch. 1 & 2 Input   
					Sensitivity   
					Control   
					Ch. 3 & 4   
					Filter Mode   
					Selection   
					(pg. 7)   
					Input Voltage   
					Selection   
					(pg. 6)   
					Status   
					Indicator   
					(pg. 10)   
					Frequency   
					Selector   
					(pg. 7)   
					(pg. 6)   
					Ch. 1 & 2   
					Filter Mode   
					Selection   
					(pg. 7)   
					Ch. 3 & 4   
					Ch. 3 & 4   
					Filter Frequency   
					Selector   
					• 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.   
					Channels 3 & 4   
					Preamp Input Jacks   
					(pg. 6)   
					Protection Status   
					Input Sensitivity   
					Control   
					Indicator   
					(pg. 10)   
					(pg. 6)   
					(pg. 7)   
					Channels 1 & 2   
					Preamp Input Jacks   
					(pg. 6)   
					Left & Right   
					Preamp Output   
					Jacks   
					Ch. 3 & 4   
					Bass Boost   
					On/Off Switch   
					(pg. 8)   
					Pre-Out Signal   
					Selection Switch   
					(pg. 8)   
					Jack for   
					Ch. 3 & 4   
					(pg. 8)   
					Remote Bass   
					Control Knob   
					(pg. 8)   
					Input Selection   
					Switch   
					(pg. 6)   
					2 
					JL AUDIO A4300   
					JL AUDIO A4300   
					3 
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				PRODUCT DESCRIPTION   
					The JL Audio A4300 is a four-channel,   
					full-range audio amplifier utilizing patented   
					Absolute Symmetry™ Class A/B technology   
					for all channels.   
					The A4300 can be operated with a wide variety   
					of source units and system configurations.   
					(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 the   
					supplied screws.   
					8) Connect the positive and negative power   
					wires to the amplifier. A fuse near the   
					amplifier is not necessary.   
					The A4300’s “+12VDC” and “Ground”   
					connections are designed to accept 8 AWG -   
					4 AWG power wire. 8 AWG is a minimum power   
					wire size for this amplifier.   
					If you are installing the A4300 with other   
					amplifiers and wish to use a single main power   
					wire, use 4 AWG or larger main power wire   
					(depending on the overall current demands of all   
					the amplifiers in the system). This 4 AWG or   
					larger power wire should terminate into a   
					distribution block mounted as close to the   
					amplifiers as possible and should connect to the   
					A4300 with 8 AWG - 4 AWG power wire.   
					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.   
					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   
					any questions, please contact your authorized   
					JL Audio dealer for assistance.   
					FUSE REQUIREMENTS   
					It is absolutely vital that the main power   
					9) Connect the remote turn-on wire   
					to the amplifier.   
					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 A4300 is being run from that power wire,   
					we recommend a 40A fuse be used. AFS (mini   
					blade fuse), AGU (big glass fuse) or MaxiFuse™   
					(big plastic-body fuse) types are recommended.   
					No fuse is required or recommended directly   
					before the amplifier power connection. If one is   
					desired, we recommend the use of a 40A fuse.   
					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 (40A for a   
					single A4300) 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 14)   
					for the recommended input sensitivity   
					setting method.   
					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.).   
					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 power wire (minimum 8 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 4 AWG   
					or larger power wire and a power distribution   
					block if additional amplifiers are being   
					installed with the A4300.   
					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 of the JL Audio ECS master   
					ground lug, XA-MGL-1 is recommended).   
					Use the same size power wire as the wire   
					connected to the “+12VDC” connection   
					(minimum 8 AWG), no longer than 36 inches   
					To connect the power wires to the amplifier,   
					first back out the set screw on the top of the   
					terminal block, 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 terminal block, 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.   
					The ground connection should be made using   
					the same gauge wire as the power connection   
					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 (XA-MGL-1).   
					Alternatively, a sheet metal screw or bolt can be   
					used with a star washer.   
					TURN-ON LEAD   
					The A4300 uses a conventional +12V remote   
					turn-on lead, typically controlled by the source   
					unit’s remote turn-on output. 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 ignition-switched circuit.   
					The A4300’s “Remote” turn-on connector is   
					designed to accept 18 AWG – 12 AWG wire. To   
					connect the remote turn-on wire to the amplifier,   
					first back out the set screw on the top of the   
					terminal block, using the supplied 2.5mm hex   
					wrench. Strip 1/2 inch (12mm) of wire and insert   
					the bare wire into the terminal block, seating it   
					firmly so that no bare wire is exposed. 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 (not the   
					insulation) is firmly gripped by the set screw.   
					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.   
					Any wires run through metal barriers (such   
					as firewalls), must be protected with a high   
					quality rubber grommet to prevent damage to the   
					insulation of the wire. Failure to do so may result   
					in a dangerous short circuit.   
					4 
					JL AUDIO A4300   
					JL AUDIO A4300   
					5 
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				INPUT SECTION   
					The A4300’s input section allows you to send   
					signal to the amplifier section through the use of   
					either two or four differential-balanced inputs.   
					Input connections are via traditional   
					RCA-type jacks.   
					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.   
					No line output converter is needed in most cases.   
					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   
					14). Doing so will result in audible distortion   
					and possible speaker damage.   
					1) “Filter Mode” Control: The A4300 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:   
					“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 A4300’s channel pairs.   
					“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 A4300’s channel pairs in a   
					bi-amplified system.   
					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 consistent with the   
					descriptions in this section.   
					FILTER CONTROLS   
					Most speakers are not designed to reproduce   
					the full range of frequencies audible by the   
					human ear. For this reason, most speaker   
					systems are comprised of multiple speakers, each   
					dedicated to reproducing a specific frequency   
					range. Filters are used to select which frequency   
					range is sent to each section of a speaker system.   
					The division of frequency ranges to different   
					speakers can be done with passive filters (coils   
					and/or capacitors between the amplifier outputs   
					and the speakers), which are acceptable and   
					commonly used for filtering between mid-   
					range speakers and tweeters. Filtering between   
					subwoofer systems and satellite speaker systems   
					is best done with active filters, which cut off   
					frequency content at the input to the amplifier.   
					Active filters are more stable than passive filters   
					and do not introduce extraneous resistance,   
					which can degrade subwoofer performance.   
					The active filter built into each channel section   
					of the A4300 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.   
					INPUT SENSITIVITY CONTROLS   
					Once the appropriate “Input Voltage” range   
					has been selected, the controls labeled “Input   
					Sens.” located in each “Channel Controls”   
					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.)   
					If you wish to send four discrete channels into   
					the A4300, simply use all four inputs (channels   
					1 & 2 and channels 3 & 4) and set the “CH 3&4   
					Input From” switch to “Discrete”.   
					If you wish to feed all four channels by using   
					only two channels of input, set the “CH 3&4   
					Input From” switch to “1&2” and use only the   
					inputs to channels 1 & 2.   
					“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 A4300’s channel pairs in a   
					bi-amplified system.   
					Input Voltage Range:   
					2) “Filter Freq. (Hz)” The filter frequency   
					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   
					chart in Appendix B (page 15).   
					A wide range of signal input voltages can be   
					accommodated by the A4300’s input sections   
					(200mV – 8V). This wide range is split up into   
					two sub-ranges, accessible via a switch located to   
					the left of the Input Connectors. Be aware that the   
					position of this switch will dictate the sensitivity   
					range for all four input channels.   
					The “Low” position on the “Input Voltage”   
					switch selects an input sensitivity range between   
					200mV and 2V. This means that the “Input   
					Sens.” rotary control will operate within that   
					voltage window. If you are using an aftermarket   
					source unit or an OEM interface processor with   
					conventional preamp-level outputs, this is most   
					likely the position that you will use.   
					Tuning Hint: If you are using the A4300 to drive   
					a subwoofer system (“LP” mode), a component   
					satellite speaker system (“HP” mode) or both,   
					80 Hz is a good baseline “Filter Freq. (Hz)”   
					setting. After properly adjusting the “Input   
					Sens.”, as outlined in Appendix A (page 14), you   
					can fine tune the “Filter Freq. (Hz)” control to   
					achieve the desired system frequency response.   
					To properly set the amplifier for maximum   
					clean output, please refer to Appendix A (page   
					14) in this manual. After using this procedure,   
					you can then adjust any or all “Input Sens.”   
					levels downward if this is required to achieve the   
					desired system balance.   
					The “High” position on the “Input Voltage”   
					switch selects an input sensitivity range between   
					800mV and 8V. This is useful for certain high-   
					output preamp level signals as well as speaker-   
					level output from source units and   
					small amplifiers.   
					6 
					JL AUDIO A4300   
					JL AUDIO A4300   
					7 
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				BASS BOOST CONTROLS   
					SPEAKER OUTPUTS   
					2) “Sum”: When the A4300 is being used to drive   
					front and rear speaker systems, this preamp   
					output mode will deliver a summed front/rear   
					stereo signal to a subwoofer amplifier, while   
					permitting fading of the front and rear speaker   
					systems from the source unit. This method   
					prevents a loss of signal to the subwoofer   
					amplifier when the system is faded to the front   
					or the rear by the head unit.   
					The A4300’s speaker outputs are designed to   
					accept 16 AWG - 8 AWG wire.   
					Each pair of the A4300’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.   
					When a pair of channels are bridged, they   
					will deliver 150W x 1 into a 4 ohm load or   
					90W x 1 into an 8 ohm load. Operating a   
					pair of bridged channels into a load lower   
					than 4 ohms is not recommended.   
					Because a bridged pair of channels requires   
					that both channels receive input, you need to   
					connect both left and right inputs to the source   
					unit. Connection of only one input will result in   
					reduced power output, increased distortion and   
					can cause the amplifier to overheat.   
					Note: Any signal delay between the front and rear   
					channels can result in a cancellation of signals   
					within certain frequency ranges when using the   
					“Sum” position. If you experience a loss of bass   
					output in the “Sum” position, compared to the   
					“1&2” position, you are likely dealing with a   
					delayed signal in either the front or rear outputs   
					of the source unit. If the front to rear delay is   
					desirable for other reasons or if it cannot be   
					defeated at the source unit, we recommend that   
					you use the “1&2” position.   
					1) “CH 3&4 Bass Boost”: Found in the “Channel   
					3 & 4 Controls” section, this switch allows the   
					user to activate a 6 dB boost centered at 48 Hz   
					for channels 3 & 4. When the “CH 3&4 Bass   
					Boost” is activated, the inputs to “CH 3 (Left)”   
					and “CH 4 (Right)” are summed to create a   
					mono signal. The “Filter Mode” switch in the   
					“Channel 3 & 4” section must be in the “LP”   
					position for the bass boost to be functional.   
					Do not do this!   
					When a pair of the A4300’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:   
					2) “ Remote Bass Port”: This port allows you to   
					connect an optional remote boost knob (sold   
					separately as 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 variable   
					range of 0 to +12 dB of boost to be selected.   
					Note: In either mode, the preamp output signal   
					is not affected by the “CH 3&4 Bass Boost”   
					processing selected for the amplifier or by any   
					crossover filter selected (if the input signal is full-   
					range, the preamp output will be full-range).   
					Speaker loads below 2 ohms nominal per   
					channel are not recommended and may cause   
					the amplifier to initiate a protection mode   
					which reduces power output.   
					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 A4300’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 A4300’s channels to drive left channel   
					speakers only and the other pair of the A4300’s   
					channels to drive right channel speakers only.   
					BRIDGING CONSIDERATIONS   
					Note: The signal level of the “Preamp Output” is   
					line-level (low voltage), regardless of the position   
					selected in the A4300’s “Input Voltage” switch.   
					An additional amplifier connected to these   
					preamp outputs should have its input voltage   
					switch set to the “Low” position.   
					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 A4300 has been designed for   
					bridging of its channel pairs without the need for   
					input inversion adaptors.   
					PRE-OUTS   
					The A4300 incorporates a pass-through   
					preamp output section, so that additional   
					amplifiers can be easily added to the system. This   
					pass-through pre-amp output can be configured   
					two different ways using the switch labeled   
					“Pre-Outs Input From”.   
					2) Left + Right Channel Information:   
					When bridged and fed by a stereo input, a pair   
					of the A4300’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   
					A4300’s channels to drive a subwoofer system   
					or a summed mono center channel.   
					To bridge a pair of channels, use the   
					1) “1&2”: The preamp output delivers the same   
					signal that is connected to the CH 1&2 Inputs.   
					This mode is useful for feeding a subwoofer   
					amplifier when the A4300 is being used to   
					drive front and rear speaker systems. In this   
					mode, the preamp output signal will depend   
					only on the input signal level of CH 1&2,   
					allowing Channels 3&4 to be faded without   
					affecting the subwoofer level. If CH 1&2 is   
					faded in this mode, the signal level of the   
					preamp output will change accordingly.   
					“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.   
					8 
					JL AUDIO A4300   
					JL AUDIO A4300   
					9 
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				AMPLIFIER STATUS INDICATOR LIGHTS &   
					PROTECTION CIRCUITRY   
					There are two status indicator lights on the   
					input / control end of the amplifier.   
					SYSTEM CONFIGURATIONS   
					Low-Voltage protection:   
					The A4300 is a 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   
					drawing on pages 18 & 19 to mark the required   
					switch positions for easy reference.   
					B) Fade Subwoofer Level vs. HF Level   
					Required: a source unit or processor with two   
					pairs of stereo outputs.   
					Input Connections: the first stereo pair source   
					unit outputs is connected to the “CH 1 (Left)”   
					and “CH 2 (Right)” inputs of the A4300. The   
					second stereo pair of source unit outputs is   
					connected to the “CH 3 (Left)” and “CH 4   
					(Right)” inputs (select “Discrete” on the “CH   
					3&4 Input From” switch).   
					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   
					amplifier section’s “Input Sens.” controls.   
					If the car’s supply voltage drops below 10   
					volts, the entire amplifier will shut itself off to   
					protect its internal circuitry. The green “Power”   
					indicator will 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,   
					turn your audio system off and have your power   
					wiring, ground connections and charging   
					system inspected.   
					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.   
					SERVICING YOUR JL AUDIO 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.   
					1) “Power” (Green): lights to indicate that the   
					amplifier is turned on and operating normally.   
					C) Subwoofer Level Control Only:   
					2) “Protect” (Red): Indicates that the amplifier   
					protection circuitry has been activated to   
					prevent product failure due to a short-circuit   
					or a dangerously low impedance connected   
					to the amplifier output(s). 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   
					reduce it maximum power output to protect its   
					circuitry, which will manifest itself as increased   
					distortion. When the problem is corrected, the   
					amplifier will return to normal operation.   
					Required: a source unit or processor with   
					one pair of stereo outputs and dedicated   
					subwoofer outputs.   
					Input Connections: the main stereo pair of   
					source unit outputs is connected to the “CH   
					1 (Left)” and “CH 2 (Right)” inputs of the   
					A4300. The source unit’s dedicated subwoofer   
					output is connected to the “CH 3 (Left)” and   
					“CH 4 (Right)” inputs (select “Discrete” on   
					the “CH 3&4 Input From” switch).   
					The A4300 can be configured to drive a bi-   
					amplified system by itself or with a separate   
					subwoofer amplifier.   
					Bi-Amplified System with one A4300   
					In this configuration, channels 3&4 of the   
					A4300 will drive subwoofers (stereo or bridged)   
					with low-pass filtering. Channels 1&2 will   
					drive component speakers in stereo with   
					high-pass filtering.   
					Result: in this mode, the user has the ability to   
					control the absolute level of the LF channels   
					relative to the HF channels.   
					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.   
					Input connection options for a bi-amplified system   
					with one A4300 are as follows:   
					Advanced Rollback Thermal protection   
					Unlike conventional thermal protection   
					systems, which shut down an amplifier when it   
					overheats, this system protects the amplifier by   
					gradually reducing power output if the amplifier’s   
					safe operating temperature is exceeded. The   
					amplifier will continue to operate and return   
					to normal power output once its temperature   
					returns to a normal range.   
					Set the “Input Sens.” in the “Channel 3 &   
					4 Controls” section with the source unit’s   
					subwoofer level control set at 3/4 of full output.   
					See Appendix A (page 14) for details.   
					JL Audio Technical Support:   
					(954) 443-1100   
					9:00 AM – 5:30 PM (Eastern Time Zone)   
					Monday - Friday   
					A) No User Adjustability:   
					Required: a basic source unit or processor   
					with one pair of stereo outputs.   
					Input Connections: a single pair of stereo source   
					unit outputs connected to the “CH 1 (Left)”   
					and“CH 2 (Right)” inputs of the A4300 (select   
					“1&2” on the “CH 3&4 Input From” switch.   
					Result: the relative level of the LF and HF   
					channels will be determined by the A4300’s   
					“Input Sens.” settings and will not be user   
					adjustable from the front of the vehicle.   
					Crossover Setup for Bi-Amplified System   
					with one A4300:   
					Once the input sections have been configured   
					appropriately, go to the “Channel 3 & 4   
					Controls”. Select “LP” (low-pass) on the “Filter   
					Mode” switch and an appropriate “Filter Freq.”   
					(80 Hz is a good starting point).   
					10   
					JL AUDIO A4300   
					JL AUDIO A4300   
					11   
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				Next, turn your attention to the “Channel 1 &   
					2 Controls” and select “HP” (high-pass) on the   
					“Filter Mode” switch and an appropriate “Filter   
					Freq.” (again, 80 Hz is a good starting point).   
					After proper adjustment of the “Input Sens.”   
					controls for both channel pairs using the method   
					shown in Appendix A (page 14), you can fine   
					tune filter frequencies and attenuate either pair   
					of channels to achieve proper balance. For precise   
					filter frequency information refer to Appendix B   
					(page 15).   
					B) Fade Subwoofer Level vs. HF Level:   
					Required: a source unit or processor with front   
					and rear pairs of stereo outputs.   
					Input Connections: one stereo pair of source   
					unit outputs is connected to the “CH 1 (Left)”   
					and “CH 2 (Right)” inputs of the A4300   
					(select “1&2” on the “CH 3&4 Input From”   
					switch). The second stereo pair of source   
					unit outputs is connected to the subwoofer   
					amplifier inputs.   
					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 A4300’s   
					“Input Sens.” settings and will not be user   
					adjustable from the front of the vehicle.   
					D) 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.   
					Set the subwoofer amplifier’s “Input Sens.”   
					with the source unit’s subwoofer level control   
					set at 3/4 of full output.   
					Crossover Setup for Bi-Amplified System with   
					one A4300 and a separate subwoofer amplifier:   
					Input Connections: one stereo pair of source   
					unit outputs is connected to the “CH 1 (Left)”   
					and “CH 2 (Right)” inputs of the A4300.   
					The second stereo pair of source unit   
					outputs is connected to the “CH 3 (Left)”   
					and “CH 4 (Right)” inputs of the A4300   
					(select “Discrete” on the “CH 3&4 Input   
					From” switch). The source unit’s dedicated   
					subwoofer output is connected to the   
					subwoofer amplifier inputs.   
					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.   
					Once the input and preamp output sections   
					have been configured appropriately, go to the   
					“Channel 1 & 2 Controls” and “Channel 3 &   
					4 Controls” You will set both control sections   
					identically to start:   
					Select “HP” (high-pass) on the “Filter Mode”   
					switch and an appropriate “Filter Freq.” (80 Hz is   
					a good starting point). Make these adjustments to   
					both control sections.   
					After proper adjustment of the A4300’s   
					“Input Sens.” controls, and the subwoofer   
					amplifier’s input sensitivity controls, you can fine   
					tune filter frequencies and attenuate either pair   
					of channels to achieve proper balance. For proper   
					adjustment of the “Input Sens.” controls of the   
					A4300 use the method shown in Appendix A   
					(page 14). For precise filter frequency information   
					for the A4300 refer to Appendix B (page 15).   
					Refer to the subwoofer owner’s manual for   
					proper adjustments.   
					Bi-Amplified System with one A4300 in   
					four-channel mode and a separate   
					subwoofer amplifier   
					This configuration requires that the separate   
					subwoofer amplifier has a built-in low-pass filter.   
					All JL Audio amplifiers have this feature.   
					In this configuration, channels 1&2 of the A4300   
					will drive front component speakerswith high-   
					pass filtering. Channels 3&4 will drive   
					rear component speakers in stereo, also with   
					high-pass filtering. The separate amplifier   
					will drive the subwoofer system with low-pass   
					filtering (80 Hz is a good starting point).   
					C) Subwoofer Level Control Only:   
					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 1 (Left)” and “CH 2 (Right)” inputs   
					of the A4300 (select “1&2” on the “CH 3&4   
					Input From” switch). The source unit’s   
					dedicated subwoofer output is connected to   
					the subwoofer amplifier inputs.   
					Input connection options for a bi-amplified   
					system with one A4300 and a separate subwoofer   
					amplifier are as follows:   
					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.   
					A) No User Adjustability:   
					Required: a basic source unit or processor with   
					one pair of stereo outputs.   
					Input Connections: a single pair of stereo source   
					unit outputs is connected to the “CH 1 (Left)”   
					and “CH 2 (Right)” inputs of the A4300 (select   
					“1&2” on the “CH 3&4 Input From” switch).   
					Connect the subwoofer amplifier inputs to   
					the preamp outputs of the A4300 (Select   
					“1&2” on the “Pre-Outs Input From” switch.   
					Alternatively, the A4300 can receive its input   
					from the subwoofer amplifier’s preamp output   
					set to “full-range” mode (if applicable).   
					Result: the relative level of the LF and front   
					and rear HF channels will be fixed by the   
					A4300’s “Input Sens.” settings (as well as the   
					subwoofer amplifier’s settings) and will not be   
					user adjustable from the front of the vehicle.   
					Set the subwoofer amplifier’s “Input Sens.”   
					with the source unit’s subwoofer level control   
					set at 3/4 of full output.   
					12   
					JL AUDIO A4300   
					JL AUDIO A4300   
					13   
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				APPENDIX A:   
					APPENDIX B:   
					APPENDIX C:   
					Input Sensitivity Level Setting   
					8) Increase the “Input Sens.” control until the   
					target voltage is observed with the voltmeter.   
					9) Once you have adjusted the A4300 to its   
					maximum low-distortion output level,   
					reconnect the speaker(s). The “Input Sens.”   
					controls can now be adjusted downward if the   
					amplifier requires attenuation to achieve the   
					desired system balance.   
					Precise Frequency Selection Chart   
					A4300 Specifications   
					Following the directions below will allow the   
					installer to adjust the input sensitivity of each   
					amplifier channel pair simply and easily in just a   
					few minutes using equipment which is commonly   
					available in installation bays.   
					“FILTER FREQ” AMP FILTER   
					General Specifications:   
					Recommended Fuse Value: 40A   
					Detent   
					Number   
					Panel   
					Marking   
					Actual   
					Freq.   
					Recommended Fuse Type: AFS, AGU or MaxiFuse™   
					Full counter-clockwise: 53   
					01 . . . . . . . . . . . . . . . . . . . . . . . . . . . .53   
					02 . . . . . . . . . . . “50”. . . . . . . . . . . .53   
					03 . . . . . . . . . . . . . . . . . . . . . . . . . . . .53   
					04 . . . . . . . . . . . . . . . . . . . . . . . . . . . .54   
					05 . . . . . . . . . . . . . . . . . . . . . . . . . . . .54   
					06 . . . . . . . . . . . . . . . . . . . . . . . . . . . .55   
					07 . . . . . . . . . . . . . . . . . . . . . . . . . . . .55   
					08 . . . . . . . . . . . “55” . . . . . . . . . . . .56   
					09 . . . . . . . . . . . . . . . . . . . . . . . . . . . .56   
					10 . . . . . . . . . . . . . . . . . . . . . . . . . . . .57   
					11 . . . . . . . . . . . . . . . . . . . . . . . . . . . .58   
					12 . . . . . . . . . . . . . . . . . . . . . . . . . . . .59   
					13 . . . . . . . . . . . . . . . . . . . . . . . . . . . .62   
					14 . . . . . . . . . . . “60”. . . . . . . . . . . .65   
					15 . . . . . . . . . . . . . . . . . . . . . . . . . . . .65   
					16 . . . . . . . . . . . . . . . . . . . . . . . . . . . .66   
					17 . . . . . . . . . . . . . . . . . . . . . . . . . . . .70   
					18 . . . . . . . . . . . . . . . . . . . . . . . . . . . .73   
					19 . . . . . . . . . . . . . . . . . . . . . . . . . . . .77   
					20 . . . . . . . . . . . “80”. . . . . . . . . . . .81   
					21 . . . . . . . . . . . . . . . . . . . . . . . . . . . .84   
					22 . . . . . . . . . . . . . . . . . . . . . . . . . . . .88   
					23 . . . . . . . . . . . . . . . . . . . . . . . . . . . .94   
					24 . . . . . . . . . . . . . . . . . . . . . . . . . . . 101   
					25 . . . . . . . . . . . . . . . . . . . . . . . . . . . 104   
					26 . . . . . . . . . . “120” . . . . . . . . . . 115   
					27 . . . . . . . . . . . . . . . . . . . . . . . . . . . 118   
					28 . . . . . . . . . . . . . . . . . . . . . . . . . . . 128   
					29 . . . . . . . . . . . . . . . . . . . . . . . . . . . 137   
					30 . . . . . . . . . . . . . . . . . . . . . . . . . . . 146   
					31 . . . . . . . . . . . . . . . . . . . . . . . . . . . 164   
					32 . . . . . . . . . . “150” . . . . . . . . . . 177   
					33 . . . . . . . . . . . . . . . . . . . . . . . . . . . 193   
					34 . . . . . . . . . . . . . . . . . . . . . . . . . . . 197   
					35 . . . . . . . . . . . . . . . . . . . . . . . . . . . 209   
					36 . . . . . . . . . . . . . . . . . . . . . . . . . . . 213   
					37 . . . . . . . . . . . . . . . . . . . . . . . . . . . 216   
					38 . . . . . . . . . . “200” . . . . . . . . . . 218   
					39 . . . . . . . . . . . . . . . . . . . . . . . . . . . 225   
					Full-clockwise: 225   
					Input Sections:   
					No. of Inputs: Two Stereo Pairs   
					Necessary Equipment   
					• Digital AC Voltmeter   
					Input Type: Differential-balanced with RCA jack inputs   
					Input Range: Switchable from 200mV - 2V RMS to   
					800mV - 8V RMS   
					• CD with a sine-wave test tone recorded at   
					0 dB reference level in the frequency range   
					to be amplified for that set of channels   
					(50 Hz for subwoofer channels, 1 kHz for a   
					midrange application). Do not use attenuated   
					test tones (-10 dB, -20 dB, etc.).   
					Do not increase any “Input Sens.” setting for   
					any amplifier channel or channel pair in the   
					system beyond the maximum level established   
					during this procedure. Doing so will result in   
					audible distortion and possible speaker damage.   
					Amplifier Section:   
					Amplifier Topology: Class A/B with patented Absolute   
					Symmetry™ dual N-Channel MOSFET output design   
					Power Supply: Unregulated MOSFET switching type   
					Rated Power at 12.5 V (Stereo, all channels driven):   
					45W RMS x 4 @ 4 ohms, 75W RMS x 4 @ 2 ohms   
					Rated Power at 12.5 V (Bridged, all channels driven):   
					90W RMS x 2 @ 8 ohms, 150W RMS x 2 @ 4 ohms   
					THD at Rated Power:   
					The Nine-Step Procedure   
					1) Disconnect the speaker(s) from the   
					amplifier’s speaker output connectors.   
					2) Turn off all processing (bass/treble, loudness,   
					EQ, etc.) on the source unit, processors (if   
					used) and amplifier. Set fader control to center   
					position and subwoofer level control to 3/4 of   
					maximum (if used to feed the A4300).   
					3) Switch the “Input Voltage” switch to “Low”   
					and turn the “Input Sens.” control all the   
					way down.   
					4) Set the source unit volume to 3/4 of full   
					volume. This will allow for reasonable gain   
					overlap with moderate clipping at full volume.   
					5) Using the chart on this page, determine the target   
					voltage for input sensitivity adjustment according   
					to the nominal impedance of the speaker system   
					connected to the amplifier outputs.   
					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 the A4300) at 3/4   
					source unit volume.   
					7) Connect the AC voltmeter to the speaker output   
					connectors of the amplifier. If the 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–).   
					It will be necessary to re-adjust the   
					“Input Sens.” for the affected channels if any   
					equalizer boost is activated after setting the   
					“Input Sens.” with this procedure. This applies   
					to any EQ boost circuit, including source unit   
					tone controls or EQ circuits. EQ cuts will not   
					require re-adjustment.   
					<0.08% @ 4 ohms per ch. (20 Hz - 20 kHz)   
					Signal to Noise Ratio: >104 dB referred to rated power   
					(A-weighted, 20 Hz-20 kHz noise bandwidth)   
					Frequency Response: 10 Hz - 25 kHz (+0, -1dB)   
					Damping Factor: >200 @ 4 ohms per ch./50 Hz,   
					>100 @ 2 ohms per ch. /50 Hz   
					Nom.   
					Target AC Voltage   
					Slew Rate: 22V/μs   
					Impedance   
					Stereo   
					Bridged   
					26.8 V   
					Power output at 14.4V supply voltage and 1% THD:   
					70W RMS x 4 @ 4 ohms (14.4V, 1% THD)   
					110W RMS x 4 @ 2 ohms (14.4V, 1% THD)   
					Rated Power (Bridged):   
					13.4 V   
					13.4 V   
					13.4 V   
					12.8 V   
					12.3 V   
					8Ω   
					6Ω   
					4Ω   
					3Ω   
					2Ω   
					25.6 V   
					24.6 V   
					140W RMS x 2 @ 8 ohms (14.4V, 1% THD)   
					220W RMS x 2 @ 4 ohms (14.4V, 1% THD)   
					not recommended   
					not recommended   
					Amplifier Filter:   
					Filter Type: State-variable, 12dB/octave Butterworth   
					with continuously variable cutoff frequency selection   
					from 50-200 Hz.   
					Configurable as Low-Pass or High-Pass. Defeatable.   
					Preamp Output:   
					Pass-through type, buffered.   
					Switch-selectable to pass signal from CH 1&2 inputs   
					only or from all four inputs (summed).   
					Dimensions(LxWxH):   
					13.8" x 9.25" x 2.50" (350mm x 235mm x 63.5mm)   
					Due to ongoing product development, all specifications are subject to   
					change without notice.   
					14   
					JL AUDIO A4300   
					JL AUDIO A4300   
					15   
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				APPENDIX D: 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 A (page 14) to set the input sensitivity for   
					maximum, low-distortion output.   
					of the A4300 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   
					extremely difficult to detect with a common DC voltmeter.   
					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   
					“+12VDC”, “Ground”, and “Remote” terminals. 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 “+12VDC” wire   
					to the “Remote” terminal to see if the amplifier turns on. If this   
					does not work, proceed to the next step.   
					“My amplifier turns on, but there is no output”   
					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   
					(example: 50 Hz for a sub bass application or 1 kHz for a full   
					range / high-pass application). A steady, sufficient voltage   
					(between 0.2 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.   
					“I get a distorted / attenuated sound coming out of the speaker(s)”   
					Check the speaker wires for a possible short, either between the   
					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   
					“Protect” 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   
					2 ohms in stereo mode (4 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.   
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					JL AUDIO A4300   
					JL AUDIO A4300   
					17   
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				INSTALLATION NOTES:   
					Use this diagram to document your amplifier’s switch and control positions.   
					18   
					JL AUDIO A4300   
					JL AUDIO A4300   
					19   
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