JL AUDIO 450/4

four-channel system amplifier

o w n e r s m a n u a l

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 amplifiers 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 (Eastern Time Zone).
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 highpower 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 products serial number. Please take the time to enter that number in the space provided below. The serial number can be found on the bottom panel of the amplifier and on the amplifier packaging. Serial Number: _______________________________
INSTALLATION APPLICATIONS This amplifier is designed for operation in vehicles with 12V, negative-ground electrical systems. Use of this product in vehicles with positive ground and/or voltages other than 12V may result in damage to the product and will void the warranty. This product is not certified or approved for use in aircraft. Do not attempt to bridge the outputs of this amplifier with the outputs of a second amplifier, including an identical one.
PLANNING YOUR INSTALLATION It is important that you take the time to read this manual and that you plan out your installation carefully.The following are some considerations that you must take into account when planning your installation. Cooling Efficiency Considerations: Your JL Audio amplifier employs an advanced type of heat management, called RealSink.This feature takes advantage of convection and radiation effects to remove heat from the amplifier circuitry. For optimum cooling performance, the vertical heat sinks located at the back of the amplifier should be exposed to as large a volume of air as possible. Enclosing the amplifier in a small, poorly ventilated chamber can lead to excessive heat build-up and degraded performance. If an installation calls for an enclosure around the amplifier, we recommend that this enclosure be ventilated with the aid of a fan. In normal applications, fan-cooling is not necessary, but you still need to follow some basic guidelines: Amplifier mounted vertically with heat sink fins pointing up: Optimum Amplifier mounted horizontally, right side up: Good Amplifier mounted horizontally, but upside down: Fair (not recommended if there is less than 1 inch (2.5 cm) clearance above the amplifier heat sinks) Amplifier mounted vertically with heat sink fins pointing laterally: Fair Amplifier mounted vertically with heat sink fins pointing down: Poor (not recommended)
CH 1&2 CH 1&2 Input Infrasonic Filter Filter Slope Sensitivity Control On/Off Switch Selection / Defeat (pg. 6) (pg. 9) (pg. 7) CH 1&2 CH 1&2 Filter Frequency Bass EQ Input Voltage Range Selector On/Off Switch Range Selector (pg. 7) (pg. 9) (pg. 6)
If mounting the amplifier under a seat, make sure there is at least 1 inch (2.5 cm) of space above the amplifier heat sink fins to permit proper cooling. Safety Considerations: Your amplifier needs to be installed in a dry, well-ventilated environment and in a manner which does not interfere with your vehicles safety equipment (air bags, seat belt systems, ABS brake systems, etc.).You should also take the time to securely mount the amplifier using the supplied screws so that it does not come loose in the event of a collision or a sudden jolt to the vehicle (20 lbs. of aluminum traveling at 60 MPH will hurt you). Stupid Mistakes to Avoid: Check before drilling any holes in your vehicle to make sure that you will not be drilling through a gas tank, brake line, wiring harness or other vital vehicle system. Do not run system wiring outside or underneath the vehicle.This is an extremely dangerous practice which can result in severe damage to your vehicle and person. Protect all system wires from sharp metal edges and wear by carefully routing them, tying them down and using grommets and loom where appropriate. Do not mount the amplifier in the engine compartment, under the vehicle, on the roof or in any other area that will expose the amplifier circuitry to the elements.

To connect the power wires to the amplifier, first back out the set screw on the top of the amplifier, using the supplied 2.5 mm hex wrench. Strip 1/2 inch (12 mm) of insulation from the end of each wire and insert the bare wire into the receptacle on the front panel of the amplifier, seating it firmly so that no bare wire is exposed.While holding the wire in place, tighten the set screw firmly, taking care not to strip the head of the screw. The ground connection should be made using the same gauge wire as the power connection (4 AWG) and should be kept as short as possible, while accessing a solid piece of sheet metal in the vehicle.The surface of the sheet metal should be sanded at the contact point to create a clean, metalto-metal connection between the chassis and the termination of the ground wire.The use of a star washer to lock down the connection is advisable. 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.

! I M P O RTA N T

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 It is absolutely vital that the main power wire(s) to the amplifier(s) in the system be fused within 18 inches (45 cm) of the positive battery post connection.The fuse value at each power wire should be high enough for all of the equipment being run from that power wire. If only the 450/4 is being run from that power wire, we recommend a 60A fuse be used. AGU (big glass fuse) or MaxiFuse (big plastic-body fuse) types are recommended. No fuse is required or recommended directly before the amplifier power connection. If one is desired, we recommend the use of a 60A AGU fuse or MaxiFuse type.
The 450/4's +12 VDC and Ground connections are designed to accept 4 AWG power wire. 4 AWG is the only recommended power wire size for this amplifier. If you are installing the 450/4 with other amplifiers and wish to use a single main power wire, use 2 AWG or 1/0 AWG main power wire (depending on the overall current demands of all the amplifiers in the system).This 2 AWG or 1/0 AWG power wire should terminate into a distribution block mounted as close to the amplifiers as possible and should connect to the 450/4 with 4 AWG power wire. Please note that smaller AWG numbers mean bigger wire and vice-versa (1/0 AWG is biggest, 2 AWG is smaller, then 4 AWG, then 8 AWG, etc.).

TURN-ON LEAD The 450/4 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 amplifiers turn-on lead can be connected to +12V via a switch that derives power from an ignition-switched circuit. The 450/4's Remote turn-on connector is designed to accept 18 AWG 8 AWG wire. 12 AWG is more than adequate for this purpose. To connect the remote turn-on wire to the amplifier, first back out the set screw on the top of the amplifier, using the supplied hex wrench. Strip 1/2 inch (12mm) of wire and insert the bare wire into the receptacle on the front panel of the amplifier, seating it firmly so that no bare wire is exposed.When using smaller wire, it may be necessary to strip 1 inch of insulation from the wire and fold the bare wire in half prior to insertion. While holding the wire in the terminal, tighten the set screw firmly, taking care not to strip the head of the screw and making sure that the wire is firmly gripped by the set screw. CH 1&2 / CH 3&4 INPUT SECTIONS The 450/4 has two separate input sections, one for CH 1&2 and another for CH 3&4. Each section contains a pair of RCA-type input jacks, an Input Voltage switch and an Input Sens. rotary control.
route the signals connected to the CH 1&2 inputs to CH 3&4 as well. If you wish to use separate inputs for CH 1&2 and CH 3&4 (to allow front-to-rear fading, for example) and the source unit is equipped with front and rear outputs, select 4ch on the Input Mode switch located in the CH 1&2 Input Section. In this mode, you must connect separate pairs of input cables to each input section. 2) Input Voltage Range: A wide range of signal input voltages can be accommodated by each of the 450/4's input sections (200mV 8V).This wide range is split up into two sub-ranges, accessible via switches located in each input section of the amplifier. Be aware that each input section's Input Voltage switch will have to be configured, regardless of how many input cables are actually feeding the amplifier. The Low position on each 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, with conventional preamp-level outputs, this is most likely the position that you will use. The High position on each 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.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.

JL AUDIO 450/4 JL AUDIO 450/4
The CH 1&2 Input Section also contains an Input Mode switch to allow operation of all four amplifier channels with one or two pairs of input signals. 1) Input Mode Switch: If you wish to operate all four channels of the 450/4 with a single pair of stereo inputs, select the 2ch position on the Input Mode switch and connect a single pair of input cables to the input jacks in the CH 1&2 Input Section. In this mode, the amplifier will
1) Filter Type Control: Located in the CH 1&2 Filter Section, this switch allows you to configure the CH 1&2 filter into one of three filter types: LP (Low-Pass): Configures the CH 1&2 filter to attenuate frequencies above the selected filter frequency. Useful for connection of subwoofer(s) to CH 1&2 in a bi-amplified system. BP (Bandpass): Configures the filter to attenuate frequencies above the selected filter frequency and below the frequency selected in the CH 3&4 HighPass Filter. This creates a true bandpass filter wellsuited for driving mid-bass or mid-range speakers in a tri-amplified system. HP (High-Pass): Configures the CH 1&2 filter to attenuate frequencies below the selected filter frequency. Useful for connection of component speakers to CH 1&2 in a bi-amplified system. 2) Filter Mode/Slope Control: This switch allows you to defeat the CH 1&2 filter or select from two filter slopes. Off: Defeats the filter for CH 1&2 completely, allowing the full range of frequencies present at the inputs to feed that pair of channels.This is useful for systems utilizing outboard crossovers or requiring full-range reproduction from that pair of channels. 12dB: Configures the filter for CH 1&2 to attenuate frequencies above or below the selected filter frequency at a rate of 12 dB per octave (Butterworth alignment).
24dB: Configures the filter for CH 1&2 to attenuate frequencies above or below the selected filter frequency at a rate of 24 dB per octave (Linkwitz-Riley alignment). Depending on the speaker system and the vehicle, different filter slopes may be required to produce a smooth transition between the sound of different speakers in the system. Experiment to find the slope which best matches the acoustic requirements of the system.The sharper 24dB setting will do a better job of protecting small speakers with limited power handling.The shallower 12dB octave setting allows the rear speakers to reproduce more low-frequency content. 3) Freq. Range Control: When thrown to the right, this switch multiplies the cutoff frequency selected by the rotary Filter Freq. (Hz) control by a factor of 10. In the x1 position, the range of the rotary control is 50 - 500 Hz (as marked). In the x10 position, the range of the rotary control is 500 Hz - 5 kHz (5000 Hz). 4) 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 charts in Appendix A (page 20) of this manual. CH 3&4 Filter Section:

to attenuate frequencies below the selected filter frequency at a rate of 12 dB per octave (Butterworth alignment). 24dB: Configures the high-pass filter for CH 3&4 to attenuate frequencies below the selected filter frequency at a rate of 24 dB per octave (LinkwitzRiley alignment). Depending on the speaker system and the vehicle, different filter slopes may be required to produce a smooth transition between the speakers in the system. Experiment to find the slope which best matches the acoustic requirements of your system.The sharper 24dB setting will do a better job of protecting small speakers with limited power handling.The shallower 12dB octave setting allows the rear speakers to reproduce more lowfrequency content. 2) Freq. Range Control: When thrown to the right, this switch multiplies the cutoff frequency selected by the rotary Filter Freq. (Hz) control by a factor of 10. In the x1 position, the range of the rotary control is 50 - 500 Hz (as marked). In the x10 position, the range of the rotary control is 500 Hz - 5 kHz (5000 Hz). 3) 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 charts in Appendix A (page 20) of this manual.
PREAMP OUTPUT SECTION The 450/4 incorporates a pass-through preamp output section, so that additional amplifiers can be added to the system.This pass-through pre-amp output can be configured three different ways using the switch labeled Signal From in the Preamp Output Section.
Voltage settings.The preamp output level is not affected by the Input Sens. rotary controls. CH 1 & 2 BASS CONTROL This section provides two basic bass processing tools for CH 1&2: a 24 dB/octave infrasonic filter at 30 Hz and a +6 dB boost circuit centered at 48 Hz. Activation of either feature automatically sums the CH 1&2 input signals to mono. (These features should only be used when driving subwoofer(s) from CH 1&2).
1) High-Pass Filter Control: This switch allows you to defeat the CH 3&4 filter or select from two different filter slopes. Off: Defeats the filter for CH 3&4 completely, allowing the full range of frequencies present at the inputs to feed that pair of channels.This is useful for systems utilizing outboard crossovers or requiring full-range reproduction from these channels. 12dB: Configures the high-pass filter for CH 3&4

Why a mono signal? If you are bridging a pair of channels and use a stereo input, the only information that will reach the amplifier stage is the common-phase portion of the signal.This may be useful for passively deriving a center-channel signal, but is not going to give you a defined left or right channel. If you are looking to reproduce a single channels signal, you must split the mono signal with a Y-adaptor and connect it to both left and right RCA inputs for the bridged channel pair. STATUS INDICATOR LIGHTS / PROTECTION CIRCUITRY There are three status indicator lights on the top of the amplifier. These are as follows: 1) Power (Green): lights to indicate that the amplifier is turned on and operating normally. 2) Thermal (Red): lights to indicate that the amplifier has exceeded its safe operating temperature, putting the amplifier into a selfprotection mode, which reduces the power output of the amplifier. The red light will shut off and the amplifier will return to normal, full-power operating mode if the heat sink temperature drops back to a safe level. 3) Low (Amber): lights to indicate that the impedance of the speaker load connected to the amplifier is lower than the optimum load impedance range for the amplifier.When this light is on, a protection circuit engages and reduces the power output of CH 1&2 or CH 3&4, depending on which channel is experiencing the problem.The amber indicator will also light when a short-circuit is detected in the speaker wiring (this can be a short between the positive and negative speaker wires or between either speaker wire and the vehicle chassis).This can be used to diagnose a short-circuit by only connecting one of the amplifier sections at a time (CH 1&2 and CH 3&4). The amber LED will light when you connect the section that is experiencing the problem and turn the volume up.
There is only one condition that will shut down an undamaged 450/4 completely If battery voltage drops below 10 volts, the entire amplifier will shut itself off.The green Power indicator on the top of the amplifier 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, have your charging system inspected to make sure it is working properly. A 0.5 or 1.0 Farad rapid-discharge capacitor connected in parallel to the amplifier power connections will minimize these short duration voltage dips in most systems that are having this problem. For information on troubleshooting this amplifier, refer to Appendix C (page 22). 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. If you have any questions about the installation or setup of the amplifier not covered in this manual, please contact your dealer or the JL AUDIO Technical Department for assistance: (954) 443-1100 9:00 AM 5:30 PM Eastern Time, Monday Friday

BI-AMPLIFIED SYSTEM WITH ONE 450/4 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 subwoofer amplifiers have this feature. In this configuration, CH 1&2 of the 450/4 will drive front component speakers (stereo 150W x 2) with high-pass filtering. CH 3&4 will drive rear component speakers in stereo (75W x 2) with highpass filtering. The separate amplifier will drive the subwoofer system with low-pass filtering (select a filter frequency of 80-90 Hz to start).The inputs of the subwoofer amplifier may or may not be connected to the preamp outputs of the 450/4, depending on which connection option you choose. Input connection options for a bi-amplifier system with one 450/4 and a separate subwoofer amplifier are as follows: A) No User Adjustability Required: a basic source unit or processor with left and right stereo outputs. Input Connections: a single pair of stereo source unit outputs is connected to the CH 1&2 inputs of the 450/4 (select 2ch on the Input Mode switch in the CH 1&2 Input Section). Connect the subwoofer amplifier inputs to the preamp outputs of the 450/4 (Select 1&2 on the Signal From switch in the Preamp Output Section). Result: the relative level of the LF and front and rear HF channels will be fixed by the 450/4s Input Sens. settings and will not be user adjustable from the front of the vehicle. 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
Set the CH 1&2 Input Sens. with the source units subwoofer level control set at 3/4 of full output. See Appendix B (page 20) for details.
outputs is connected to the CH 1&2 inputs of the 450/4 (select 2ch on the Input Mode switch in the CH 1&2 Input Section).The second stereo pair of source unit outputs is connected to the subwoofer amplifier inputs. In this mode, the 450/4s preamp output is not used. Result: with this option, the user has the ability to fade the level of the subwoofer amplifiers input relative to the HF channels, but cannot control front-to-rear fading of the HF channels.The relative level of the front and rear HF channels will be fixed by the 450/4s Input Sens. settings and will not be user adjustable from the front of the vehicle. C) Fade HF Front to Rear with Non-Fading Subwoofer Level Required: a source unit or processor with front and rear pairs of stereo outputs. Input Connections: one stereo pair of source unit outputs is connected to the CH 1&2 inputs of the 450/4 (select 4ch on the Input Mode switch in the CH 1&2 Input Section).The second stereo pair of source unit outputs is connected to the CH 3&4 inputs of the 450/4. Connect the subwoofer amplifier inputs to the preamp outputs of the 450/4 (Select ALL on the Signal From switch in the Preamp Output Section). Result: with this option, the user has the ability to fade the HF signals from front-to-rear without fading the signal to the subwoofer amplifier. D) 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&2 inputs of the 450/4 (select 2ch on the Input Mode switch in the CH 1&2 Input Section).The source units dedicated subwoofer output is connected to the subwoofer amplifier inputs. In this mode, the 450/4s preamp output is not used.

BI-AMPLIFIED 3.1 SYSTEM WITH ONE 450/4 IN THREE-CHANNEL MODE AND A SEPARATE SUBWOOFER AMPLIFIER This configuration requires a separate subwoofer amplifier with a built-in low-pass filter. All JL Audio subwoofer amplifiers have this feature. The separate amplifier will drive the subwoofer system with low-pass filtering (select a filter frequency of 80-90 Hz to start).The inputs of the subwoofer amplifier will be connected to the preamp outputs of the 450/4 or to the source unit or multi-channel processor directly. In this configuration, CH 1&2 of the 450/4 will drive front-left and front-right component speakers (stereo 150W x 2) with high-pass filtering. CH 3&4 will be bridged mono to drive a center-front component speaker system (150W x 1) with high-pass filtering. All three channels will have equal power at 3 4. Input connection options for bi-amplified 3.1 system with one 450/4 and a separate subwoofer amplifier: A) Real Left-Center-Right Channels and Subwoofer with Multi-Channel Source Required: a multi-channel processor or source unit (Dolby Digital, Dolby ProLogic II, dts, etc.) with center channel output. Input Connections: the left-front and right-front source unit outputs are connected to the CH 1&2 inputs of the 450/4 and the front-center channel output of the source unit or processor is connected to the CH 3&4 inputs of the 450/4 (select 4ch on the Input Mode switch in the CH 1&2 Input Section). Use a Y-adaptor to feed both RCA jacks on the amplifier from the single signal cable. Most multi-channel processors and source units are also equipped with a dedicated subwoofer output and subwoofer level control. Connect this subwoofer output directly to the subwoofer amplifiers inputs. The 450/4s preamp outputs are not used.
Result: True left, center and right channels with multi-channel material, derived center channel with stereo material. Rear-surround channels are unused. User adjustability of left, center and right channels depends on source unit/processor. Subwoofer level is user adjustable.
Set the subwoofer amplifiers Input Sens. with the source units subwoofer level control set at 3/4 of full output. Refer to the subwoofer amplifier owners manual for proper adjustment.
The Summed Center Channel methods outlined below do not create a true center channel, they simply sum left and right signals to the center speaker system. This is not as desirable as a true center channel from a multi-channel source, but it can be used to create a convincing sound stage in some applications. B) Summed Center Channel, No User Adjustability Required: a basic source unit or processor with left and right stereo outputs. Input Connections: a single pair of stereo source unit outputs, connected to the CH 1&2 inputs of the 450/4 (select 2ch on the Input Mode switch in the CH 1&2 Input Section). Connect the subwoofer amplifier inputs to the preamp outputs of the 450/4 (Select 1&2 on the Signal From switch in the Preamp Output Section). Result: the relative level of all channels will be fixed by the 450/4s Input Sens. settings and will not be user adjustable from the front of the vehicle.

C) Fade Between Summed Center Channel Level and Left/Right Level with Non-Fading Subwoofer Level Required: a source unit or processor with front and rear pairs of stereo outputs. Input Connections: one pair of stereo source unit outputs is connected to the CH 1&2 inputs of the 450/4 (select 4ch on the Input Mode switch in the CH 1&2 Input Section). A second pair of source unit outputs is connected to the CH 3&4 inputs. Connect the subwoofer amplifier inputs to the preamp outputs of the 450/4 (Select ALL on the Signal From switch in the Preamp Output Section). Result: with this option, the user has the ability to adjust the relative level of the Summed Center Channel input relative to the Left and Right channel pair via the source units fader control. Subwoofer is non-fading. D) Fade Between Summed Center Channel Level and Left/Right Level with Separate Subwoofer Level Control Required: a source unit or processor with front and rear pairs of stereo outputs plus a dedicated subwoofer output. Input Connections: one pair of stereo source unit outputs is connected to the CH 1&2 inputs of the 450/4 (select 4ch on the Input Mode switch in the CH 1&2 Input Section). A second pair of source unit outputs is connected to the CH 3&4 inputs.The source units dedicated subwoofer output is connected to the subwoofer amplifiers inputs. In this mode, the 450/4s preamp output is not used. Result: with this option, the user has the ability to fade between the Summed Center Channel level and the Left and Right channel levels via the source units fader control and also has the ability to control the absolute level of the subwoofer
channel relative to the three HF channels with the source units subwoofer level control.
Set the subwoofer amplifiers Input Sens. with the source units subwoofer level control set at 3/4 of full output. Refer to the subwoofer amplifier owners manual for proper adjustment. Crossover setup for bi-amplified 3.1 system with one 450/4 and a separate subwoofer amplifier: Once the input and preamp output sections have been configured appropriately, go to the CH 1&2 Filter Section. Select x1 on the Freq. Range switch, HP (high-pass) on the Filter Type switch and 12dB or 24dB on the Filter Mode/Slope switch and an appropriate Filter Freq. (80-90 Hz is a good starting point). The Infrasonic Filter and Bass EQ features cannot be used in this mode. Next, turn your attention to the CH 3&4 Input Section and select x1 on the Freq. Range switch, HP (high-pass) on the Filter Type switch and 12dB or 24dB on the Filter Mode/Slope switch and an appropriate Filter Freq. (again, 8090 Hz is a good starting point). After proper adjustment of the 450/4s CH 1&2 and CH 3&4, and the subwoofer amplifiers Input Range and Input Sens., you can fine tune filter frequencies and slopes and attenuate the center channel or the left and right channel pair with the Input Sens. controls to achieve proper balance. For proper adjustment of the Input Sens. controls of the 450/4 use the method shown in Appendix B (page 20). For precise filter frequency information for the 450/4 refer to Appendix A (page 20). Refer to the subwoofer amplifier owners manual for proper adjustments.

subwoofer amplifier inputs. In this mode, the 450/4s preamp output is not used. Result: the user has the ability to control the absolute level of the subwoofer channel relative to the MF and HF channels.
Set the subwoofer amplifiers Input Sens. with the source units subwoofer level control set at 3/4 of full output. Refer to the subwoofer amplifier owners manual for proper adjustment. Crossover setup for tri-amplified 3.1 system with one 450/4 and a separate subwoofer amplifier: Once the input and preamp output sections have been configured appropriately, go to the CH 1&2 Filter Section of the 450/4. These settings will determine the high-pass cutoff and slope of the bandpass filtering applied to the MF (mid-frequency) channels. Select x1 on the Freq. Range switch, BP (bandpass) on the Filter Type switch and 12dB or 24dB on the Filter Mode/Slope switch and an appropriate Filter Freq. (80-90 Hz is a good starting point). The Infrasonic Filter and Bass EQ features cannot be used in this mode. Next, turn your attention to the CH 3&4 Input Section. These settings will determine the high-pass cutoff and slope of the high pass filtering applied to the HF (high-frequency) channels as well as the lowpass cutoff frequency and slope for the MF channels bandpass filter. Select x1 on the Freq. Range switch if your desired MF to HF crossover frequency is below 500 Hz. Select x10 on the Freq. Range switch if your desired MF to HF crossover frequency is above 500 Hz. Select HP (high-pass) on the Filter Type switch and 12dB or 24dB on the Filter Mode/Slope switch and an appropriate Filter Freq.
After proper adjustment of the 450/4s CH 1&2 and CH 3&4, and the subwoofer amplifiers Input Range and Input Sens., you can fine tune filter frequencies and slopes and attenuate the LF, MF and HF channel pair or with the Input Sens. controls to achieve proper balance. For proper adjustment of the Input Sens. controls of the 450/4 use the method shown in Appendix B (page 20). For precise filter frequency information for the 450/4 refer to Appendix A (page 20). Refer to the subwoofer amplifier owners manual for proper adjustments.
APPENDIX A: Precise Frequency Selection Chart

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 RCA cables from the amplifier prior to this test).The frequency used should be in the range that is to amplified by the channels being tested (example: 50 Hz for a sub bass amplifier channel and 1 kHz for a full range amplifier channel). A steady voltage should be present at the output of the RCA cables. If you are receiving a sufficient voltage (between 0.2 and 8.0-volts), check to ensure that the speaker wires are making a good connection with the metal inside the amplifier. The connectors are designed to accept up to an 8 AWG wire. If you are using significantly smaller wire (14 AWG or smaller), you may have difficulty making an adequate connection. In this case, you may find it necessary to fold the wire over once (or twice!) so as to make a solid connection. Make sure to strip the wire to allow for a sufficient connection with the input or output of the amplifier. Check the output of the amplifier. Using the procedure explained in the previous check item (after plugging the RCA 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. 5-volts 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 above. MY AMPLIFIERS 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 amplifier terminal. Check the RCA connectors to ensure that both the center pin and the outer shield are making good contact with the input jacks on the amplifier.
HOW DO I PROPERLY SET THE INPUT SENSITIVITY ON MY AMPLIFIER Please refer to Appendix B (page 20) to set the input sensitivity for maximum, unclipped output.
APPENDIX D: 450/4 Specifications
GENERAL SPECIFICATIONS: Recommended Fuse Value: 60A Recommended Fuse Type: AGU or MaxiFuse INPUT SECTIONS: No. of Inputs: Two Stereo Pairs (CH 1&2, CH 3&4) Input Type: Differential-balanced with RCA jack inputs Input Range: Switchable from 200mV - 2V RMS to 800mV - 8V RMS CHANNELS 1 & 2: Amplifier Topology: Class AB with patented Absolute Symmetry dual N-Channel MOSFET output design Power Supply: Independent, pulse width modulationregulated switching power supply with multistage impedance optimizing circuitry. Rated Power (Stereo): 150W RMS x 2 @ 1.5-4 (11V - 14.5V) Rated Power (Bridged): 300W RMS x 1 @ 3-8 (11V - 14.5V) THD at Rated Power: <0.03% @ 4 per channel (20 Hz-20 kHz) Signal to Noise Ratio: >108.5 dB referred to rated power (A-weighted, 20 Hz-20 kHz noise bandwidth) Frequency Response: 5 Hz - 30 kHz (+0, -1dB) Damping Factor: >200 @ 4 per ch. / 50 Hz, >100 @ 2 per ch. / 50 Hz Slew Rate: 25V/s CH 1&2 Filter: State-variable, 12 dB/octave Butterworth or 24 dB/octave Linkwitz-Riley Low-Pass or High-Pass with continuously variable cutoff frequency from 50 - 500 Hz, switchable to a range of 500 - 5000 Hz, via x10 switch. Can also be cascaded from Channel 3&4 filters cutoff frequency to operate as a bandpass filter for tri-amp configurations. Defeatable. LF Boost: Single-band, fixed-frequency (48 Hz), fixed Q +6 dB boost. Defeatable. Port for optional remote bass control to provide variable boost control from 0 to +15 dB. Infrasonic Filter: 24 dB/octave @ 30 Hz, defeatable. Due to ongoing product development, all specifications are subject to change without notice. DIMENSIONS: (LxWxH): 19.7" x 9.25" x 2.36" (500mm x 235mm x 60mm) PREAMP OUTPUT: 2-Channel pass-through type, switch-selectable to pass signal from CH 1&2 inputs only, from CH 3&4 inputs only or from all four inputs (summed). CHANNELS 3&4: Amplifier Topology: Class AB with patented Absolute Symmetry dual N-Channel MOSFET output design Power Supply: Independent, pulse width modulationregulated switching power supply with multistage impedance optimizing circuitry. Rated Power (Stereo): 75W RMS x 2 @ 1.5 - 4 (11V - 14.5V) Rated Power (Bridged): 150W RMS x 1 @ 3 - 8 (11V - 14.5V) THD at Rated Power: <0.03% @ 4 per channel (20 Hz - 20 kHz) Signal to Noise Ratio: >108.5 dB referred to rated power (A-weighted, 20 Hz - 20 kHz noise bandwidth) Frequency Response: 5 Hz - 30 kHz (+0, -1 dB) Damping Factor: >200 @ 4 per ch. / 50 Hz, >100 @ 2 per ch. / 50 Hz Slew Rate: 25V/s Channel 3&4 Filter: State-variable, 12 dB/octave Butterworth or 24 dB/octave Linkwitz-Riley High-Pass with continuously variable cutoff frequency from 50 - 500 Hz, switchable to a range of 500 - 5000 Hz, via x10 switch.

INSTALLATION NOTES: Use this diagram to document your amplifiers switch and control positions.
LIMITED WARRANTY - AMPLIFIERS (USA) JL AUDIO warrants this product to be free of defects in materials and workmanship for a period of ninety (90) days from the original date of purchase. The warranty term is extended to two (2) years if installation is performed or approved by an authorized JL AUDIO dealer (proof of installation or approval required on purchase receipt). This warranty is not transferrable and applies only to the original purchaser from an authorized JL AUDIO dealer. Should service be necessary under this warranty for any reason due to manufacturing defect or malfunction, JL AUDIO will (at its discretion), repair or replace the defective product with new or remanufactured product at no charge. Damage caused by the following is not covered under warranty: accident, misuse, abuse, product modification or neglect, failure to follow installation instructions, unauthorized repair attempts, misrepresentations by the seller.This warranty does not cover incidental or consequential damages and does not cover the cost of removing or reinstalling the unit(s). Cosmetic damage due to accident or normal wear and tear is not covered under warranty. Warranty is void if the products serial number has been removed or defaced. Any applicable implied warranties are limited in duration to the period of the express warranty as provided herein beginning with the date of the original purchase at retail, and no warranties, whether express or implied, shall apply to this product thereafter. Some states do not allow limitations on implied warranties, therefore these exclusions may not apply to you.This warranty gives you specific legal rights, and you may also have other rights which vary from state to state. If you need service on your JL AUDIO product: All warranty returns should be sent to JL AUDIO s Amplifier Service Facility freight-prepaid through an authorized JL AUDIO dealer and must be accompanied by proof of purchase (a copy of the original sales receipt). Direct returns from consumers or non-authorized dealers will be refused unless specifically authorized by JL AUDIO with a valid return authorization number. Warranty expiration on products returned without proof of purchase will be determined from the manufacturing date code. Coverage may be invalidated as this date is previous to purchase date. Non-defective items received will be returned freight-collect. Customer is responsible for shipping charges and insurance in sending the product to JL AUDIO. Freight damage on returns is not covered under warranty.
For Service Information in the U.S.A. please call: JL Audio customer service: (954) 443-1100 during normal business hours (9:00 AM 5:30 PM Eastern Time) JL Audio, Inc 10369 North Commerce Pkwy. Miramar, FL 33025 (do not send product for repair to this address) International Warranties: Products purchased outside the United States of America are covered only by that countrys distributor and not by JL Audio, Inc.

Absolute Symmetry Class AB Amplifier Circuit is covered by U.S. Patent #6,294,959 and is pending in the countries listed below. Austria, Belgium, Brazil, Canada, China, France, Germany, Indonesia, Italy, Japan, Republic of Korea, Mexico, Netherlands, Norway, Russian Federation, Singapore, Sweden, Switzerland, United Kingdom, and all other PCT countries. JL4504MAN-CH-10-2002-Rev1

ME New Products Ad

11/26/02

11:43 PM

Page 2

A New Class

-series Amplifier Features (all models):
Patented Absolute Symmetry Class AB amplifier circuits Fully variable 12 dB / octave active filters (Low-Pass or High-Pass) On-board 0 or +6dB Bass Boost with Remote Bass Control Port Pass-through Preamp Outputs (except e6450) High-level inputs for simple interfacing with OEM systems

The all-new amplifiers.

6450 six-channel full-range amplifier:
Rated Power at 12.5 V: Stereo: 6 x 45 Watts RMS at x 75 Watts RMS at 2 Bridged: 3 x 150 Watts RMS at 4 L x W x H: 17.7" x 9.25" x 2.36"
Captive-wire power connectors (up to 4 AWG) and speaker connectors (up to 8 AWG)
4300 four-channel full-range amplifier:
Rated Power at 12.5 V: Stereo: 4 x 45 Watts RMS at x 75 Watts RMS at 2 Bridged: 2 x 150 Watts RMS at 4 L x W x H: 13.8" x 9.25" x 2.36"
Ideal for small subwoofer systems or center channel applications!
1200 monoblock full-range amplifier:
Rated Power at 12.5 V: 1 x 120 Watts at x 200 Watts at 2 L x W x H: 9.8" x 9.25" x 2.36"
2150 two-channel full-range amplifier:
Rated Power at 12.5 V: Stereo: 2 x 45 Watts RMS at x 75 Watts RMS at 2 Bridged: 1 x 150 Watts RMS at 4 L x W x H: 9.8" x 9.25" x 2.36"
450/4 four-channel system amplifier
Dual, independent R.I.P.S. power supplies optimize output power in each channel section. Patented Absolute Symmetry Class AB amplifier circuit (all channels) Staggered power distribution is ideal for sub/satellite or front/rear satellite applications. Can be configured as 150W x 3 @ 4 to drive left, center and right satellites. Differential-Balanced Input Topology (2 pairs of inputs) Fully-variable (50 Hz-5 kHz), selectable slope (12dB or 24dB/octave) crossover design Preamp Outputs (1 pair) with selectable sourcing Bass Boost and Infrasonic Filter on CH 1&2 Rated Power (stereo): CH 1&2: 150 W RMS x 2 @ 1.5-4 (11V-14.5V) CH 3&4: 75 W RMS x 2 @ 1.5-4 (11V-14.5V) Rated Power (bridged): CH 1&2: 300W RMS x 1 @ 3-8 (11V-14.5V) CH 3&4: 150W RMS x 1 @ 3-8 (11V-14.5V) Dimensions (L x W x H): 19.7" x 9.25" x 2.36"

Big Block

The latest addition to the slash amplifier line.
250/1 300/2 300/4 450/4 500/1 500/5 1000/1