About the JL Audio HD Series HD900/5
Small amps, big power
Small amps, big power
JL Audio's HD Series amplifiers offer high performance from an ultra-compact chassis. These Class D amplifiers use less power, take up less space, and generate less heat than traditional amp designs — you can even stack them up to create a sweet-looking installation.
JL Audio technology goes to work for you
HD Series amplifiers reproduce your music with exceptional accuracy, so you'll hear high-fidelity sound even under the most demanding conditions. JL Audio uses Single Cycle Control™ technology to eliminate the excessive signal distortion that's plagued Class D amplifiers in the past. Differential-balanced inputs eliminate noise before it hits the preamp stage, and allow you to connect the amp to just about any in-dash stereo. You'll hear clear, true, studio-quality audio, exactly what you expect from JL Audio.
Power your entire system with one compact amp
The 5-channel HD900/5 amplifier pushes 100 watts RMS per channel to your front and rear full-range speakers, plus 500 watts RMS to a sub — all from a 2" tall chassis that's about the size of a sheet of computer paper. Or, you can bridge the front and rear channels to drive 150 watts RMS into two speakers, while still running your sub at 500 watts.
The regulated power supply allows this amp to deliver its rated power to a wide range of impedances, even when voltage levels drop during heavy use. Removable power and speaker plugs make it easy to pop this amp out if you need the space in your cargo area.
Some extra touches
You can use JL Audio's optional stack kit to mount one HD Series amp on top of another, so you can maximum power from minimum space. JL's wired remote allows you to control your HD amp's volume from your front seat.
- 5-channel amplifer
- 100 watts RMS x 4 at 4 ohms + 500 watts RMS x 1 (at 1.5-4 ohms)
- 75 watts RMS x 4 (at 1.5-3 ohms) + 500 watts RMS x 1 (at 1.5-4 ohms)
- 150 watts RMS x 2 bridged (at 3-6 ohms) + 500 watts RMS x 1 at (1.5-4 ohms)
- variable high-pass filter on front and rear channels (50-500 Hz, 12 or 24dB/octave)
- variable low-pass filter on subwoofer channel (50-500 Hz, 12 or 24dB/octave)
- subsonic filter on sub channel (24 dB/oct at 30 Hz)
- removable power and speaker plugs
- optional wired remote for level control
- optional HD stacking kit for stacking multiple HD amps together
- Class D amplifier design
- MOSFET power and output stages
- differential-balanced inputs eliminate noise from your vehicle's electrical system
- speaker- and preamp-level inputs (speaker-level input requires an optional adapter)
- preamp outputs
- 4-gauge power and ground leads and a 60-amp fuse recommended wiring and hardware not included with amplifier
- no onboard fuses when installing multiple amps in a system, an additional 60-amp in-line fuse between the distribution block and the amplifier is recommended
- 10-3/4"W x 1-15/16"H x 8-5/16"D
- warranty: 2 years
- Our 60-day money-back guarantee
- MFR # 98223
What's in the box:
- 5-Channel class-D full-range amplifier
- Power/Ground/Turn-On plug
- 3 Speaker connection plugs
- 3mm Allen-wrench
- 5mm Allen-wrench
- Mounting bolts
- Owner's Manual
JL Audio HD Series HD900/5 reviews
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More details on the JL Audio HD Series HD900/5
Features & specs
|RMS Power Output (Watts x Channels)||
100 x 4 |
500 x 1
|Peak Power Output (Watts x Channels)||N/A|
|Power at 2 Ohms (Watts x Channels)||75 x 4|
|Bridged Power (Watts x Channels)||150 x 2|
|Minimum Impedance Bridged||3|
|Minimum Impedance Unbridged||1.5|
|Best Frequency Response||12-28K Hz|
|THD at Rated RMS Power||0.03%|
|Signal to Noise Ratio||108 dB|
|Low-Pass Crossover Frequency||50-500Hz (ch 5)|
|Low-Pass Slope (dB/octave)||12 or 24 dB/oct|
|High-Pass Crossover Frequency||50-500Hz (ch 1-4)|
|High-Pass Slope (dB/octave)||12 or 24 dB/oct|
|Bass Boost Frequency||N/A|
|Speaker Level Inputs||RCA|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
Five-Channel Full-Range Amplifier: The JL Audio HD900/5 is a Class D five-channel, full-range amplifier that is rated at 75 to 100 Watts RMS x 4-channel (front/rear) and 500 Watts x 1-channel (subwoofer) in 1.5-4-ohm at 20 to 20kHz with a signal-to-noise-ratio of 108 dB and a total harmonic distortion of 0.03% while receiving 11 to14.5 Volts. The front and rear channels of the amplifier can also be bridged to output 150-200 Watts RMS x 2-channel in 3 to 8-ohms.
High-Fidelity Class D (HD) With Single-Cycle Control: The JL Audio HD900/5 utilizes patented Single Cycle Control Class D technology for all channels. This technology delivers reference-grade sonic performance while requiring far less current from the vehicle's electrical systems than a conventional amplifier. Single Cycle Control is a unique approach to controlling a full-range Class D amplifier. By tracking the audio signal, comparing it to the real PWM waveform and then correcting it in each and every cycle (over 400,000 times per second), a multitude of distortion-causing mechanisms can be tightly controlled to enable pristine amplification. While there are certainly less expensive ways to make a full-range switching amplifier, no other Class D control system works faster or more accurately than Single Cycle Control.
Compact/Efficient Design: The JL Audio Class D amplifier on average is 13% smaller overall and over 1/2-inch shorter in height than most class AB amplifiers. The HD900/5 features outstanding overall efficiency (80% at 1/2 rated power) which allows for huge power from a tiny chassis and is easy on your vehicle's charging system, drawing 60% less current than a class AB design of equal power.
R.I.P.S. (Regulated, Intelligent Power Supply): R.I.P.S. stands for "Regulated, Intelligent Power Supply" and is a central feature of the JL Audio's JL Audio HD amplifier. The JL Audio R.I.P.S. System ensures consistent power delivery over a wide range of battery voltages and load impedances. This technology provides optimum power at any impedance level between 1.5 ohm to 4 ohm per channel and at any vehicle voltage level between 11V and 14.5V.
- Regulated Power Supply: "Regulated" means that the power supply adjusts its operation so as to maintain the amplifier's rated power output and low distortion operation over a wide range of vehicle voltages (11V-14.5 V). This allows the JL Audio JL Audio HD amplifier's the rail voltage and clean power output to remain stable in real-world car-audio systems, resulting in superior fidelity and stability.
- Intelligent Power Supply: The "Intelligent" portion of the R.I.P.S. System is a circuit that actually monitors output current to optimize the amplifier's output power over a wide range of load impedances (1.5 ohm to 4 ohm per channel). The R.I.P.S. System detects the actual impedance being driven and adjusts output rail voltages to deliver optimum output. The entire process is seamless, automatic, and results in incredible dynamics for satellite channels and consistent power output for a wide range of subwoofer configurations. It also takes into account the real impedance of your car-audio system, rather than relying on often inaccurate assumptions based on a speaker's rated impedance.
RealSink Heat Management With Rollback Protection: This JL Audio amplifier employ and advanced type of heat management, called RealSink. This features takes advantage of convection and radiation effects to remove heat from the amplifier circuitry. For optimum cool performance, the vertical heat sinks located at the sides of the amplifier should be exposed to as large a volume of air as possible. If a JL Audio HD amplifier should ever reach an unsafe temperature, its unique Advanced Rollback Protection circuit also adjusts power until the amplifier cools down, without ever shutting your music down.
Differential-Balanced Inputs: The JL Audio amplifier features differential-balanced input architecture to effectively control noise and ensure compatibility with a wide variety of source units, including many OEM systems. Without resorting to line output converters, you can directly connect most OEM source units to the JL Audio amplifier without creating any noise or compatibility issues. Unlike conventional single-ended inputs, the differential-balanced design does not connect one side of the audio signal to chassis ground. This eliminates any voltage sensitivity between one input terminal and ground and greatly reduces the incidence of alternator whine in a typical car audio installation. The JL Audio HD amplifier provides range switching on each of its inputs via the "Input Voltage" switch. This permits connection to a wide range of source voltages while retaining excellent sensitivity setting precision.
Note: You will need three speaker wire to RCA adaptors (136XDCLR2S, sold separately) to connect this amplifier to your headunit via speaker-level.
Protection Circuitry With Status Indicator Lights: There is a single multi-color LED on the control panel of the amplifier to indicate the amplifier's operating status.
- Flashing Green: When the LED is flashing green, the amplifier is powering up and audio output is muted.
- Constant Green: This LED lights green to indicate that the amplifier is turned on and operating normally.
- Constant Red: This Red LED lights to indicate that the amplifier has exceeded its safe operating temperature, putting the amplifier into a shelf-protection 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.
- Constant Yellow: This amber LED lights to indicate that the impedance of the speaker load connected to the amplifier is lower than the optimum impedance load range for the amplifier. When this light is on, a protection circuit engages and reduces the power output of the amplifier. The amber indicator will also light when a short-circuit is detected in the speaker wiring.
- Alternating Red/Green: The LED alternated between Red and Green to indicate that the amplifier is experiencing a fault that may require service of the amplifier, its wiring, or the vehicle's operating system. Audio is muted when this fault occurs.
Note: There is only one condition that will shut down the HD900/5 completely and that is if the battery voltage of your vehicle drops below 10 volts.
Mounting Options: The HD900/5 has two mounting option to choose from during installation.
- Standard Mounting: The standard method of mounting requires removal of the four corner caps with the included hex-wrench. Using the appropriate mounting screws (not included), you can then secure the amplifier in all four corners and replace the corner caps.
- Lateral Mounting Feet: Lateral Mounting Feet are also included with the HD900/5 to provide an alternative mounting option. Each mounting foot should be attached to the bottom of the amplifier by screwing the provided bolts into the bottom of the amplifier and up into the corner cap with the supplied hex-wrench. Then, using the appropriate mounting screws (not included), you can secure the amplifier by its four lateral mounting feet.
Control Panel Cover: The HD900/5 features a Control Panel Security Cover which protects and hides the amplifier's controls. When installed, the cover ensures that the amplifier's settings are not accidentally changed while creating a clean aesthetic look for the amplifier and your installation. The control panel security cover is pre-installed at the factory and must be temporarily removed for access the amplifier's controls. The security cover is secured by a single hex-head screw.
Simplified Gain Setting: The amplifier's R.I.P.S. feature also allows for easy gain setup. Because the amplifier will always deliver the same amount of power within its operational range of impedances and supply voltages, the maximum, unclipped output is very predictable. This makes setting the gain level of the amplifier via the input sensitivity control very simple. All you need is Digital AC Voltmeter (142TK12V, sold separately) and a Test CD Disc (503CD104, sold separately) 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).
Flexible Input Section And Active Crossover Network: The JL Audio HD amplifier provides a flexible input section and a comprehensive crossover network to fine tune your system effectively and accurately. The variable filter design employed in the JL Audio HD amplifier crossover sections allow you to seamlessly switch slopes, easily change filter frequencies and address what frequencies the preamp outputs will pass. The HD900/5 offers the following independent crossover adjustments for the front, rear, and subwoofer channels along the unit's front panel, behind a removal cover plate.
- Input Mode: This switch allows operation of all five amplifier channels with only one pair of input signals (2ch); with independent front and rear input signal pairs (4ch); or with discrete front, rear, and subwoofer signal pairs (6ch).
- Input Voltage: This switch allows you to choose between using a low-level input signal (200mV-8V) or high-level input signal (200mv-2V).
- High-Pass or Low-Pass Filter: The HD900/5 has three individually adjustable filter controls for the Front, Rear, and Subwoofer channels. The Front and Rear filters are high-pass filters (attenuate low frequencies), while the Subwoofer channel filter is a low-pass filter (attenuates high frequencies). For each filter, you can select from a shallow (12dB/oct) filter slope or a more aggressive (24dB/oct) slope.
- Filter Frequency: This control selects the frequency at which each high-pass or low-pass filter begins to attenuate the signal and refers specifically the frequency at which output has been attenuated by -3dB. You can select from 50-500Hz.
- Infrasonic Filter (subwoofer only): The Infrasonic Filter is a 24-dB/oct high-pass filter, with a fixed cutoff frequency of 30Hz. This filter is designed to conserve amplifier power and protect subwoofer systems, without audibly degrading the subwoofer's bass output.
Power/Ground/Turn-On Plug: The amplifier features a Power/Ground/Turn-On plug which detaches from the amplifier to make connecting your power, ground, and remote turn-on lead wires more convenient. Once your connections are made the Power/Ground/Turn-On connector simply plugs into the amplifier.
- Power and Ground: The JL Audio amplifier's set-screw Power and Ground connections found on the detachable Power/Ground/Turn-on plug are designed to accept 4 AWG power wire. A hex-wrench is supplied for making connections.
- Remote Turn-On: The JL Audio HD amplifier's set-screw turn-on lead found on the Power/Ground/Turn-on plug will accept 18 to 12 AWG wire. A hex-wrench is supplied for making connection.
Note: The Amplifier is not equipped with a fuse. An external 60-amp AFS, AGU, or MAXI fuse (not included) must be installed on the power wire. If a wiring kit is used which includes a fuse with a value other than 60-amps, the original should be replaced with a 60-amp fuse
Speaker Output Plugs: The amplifier features three Speaker Output plugs (Front/Rear/Sub) which detach from the amplifier for easier speaker wire connection. Once your speaker wires are connected to these plugs, they simply push into the amplifier. The front and rear speaker output plugs feature four set-screw terminals, while the subwoofer speaker output plug features two set-screw terminals. The HD900/5 amplifier's ten set-screw speaker terminals found on the Speaker Output plugs will accept 16 to 12 AWG speaker wire. A hex-wrench is supplied for making connections.
Preamp Inputs: The amplifier features three sets of differential-balanced RCA jack inputs (Front/Rear/Sub). The amplifier features a dedicated Input Sensitivity gain control for the front, rear, and subwoofer channels of the amplifier. These controls are designed to match the input sensitivity of the HD900/5 to the specific signal source that is feeding it. The amplifier's input level can be set independently for the front and rear channels to Low (200mV-2V RMS) when connecting the amplifier to a low-level preamp signal or set to High (800mV-8V RMS) when connecting the amplifier to a high-level speaker signal.
Remote Level Control: The amplifier features a standard telephone connector for adding an optional wired remote level control. With the addition of the optional wired Remote Level Control (136HDRLC, sold separately), you can control the volume of one or both channel pairs of the HD900/5 form the front of your vehicle. This is useful for subwoofer level control or even as a master volume control for your system. If desired, multiple HD amplifiers can be controlled from a single HD-RLC controller using a simple phone line splitter and multiple phone cables (all sold separately).
Note: All inputs and outputs are located on the rear side of the amplifier to make installation of the amplifier simple and neat.
The JL Audio HD Series HD900/5 replaces these items
- 150 watts RMS x 2 bridged + 500 watts RMS x 1
- preamp and speaker-level inputs
- variable high- and low-pass filters (50-500 Hz, 12 or 24dB/octave)
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