About the JL Audio JX400/4D
Power your music
Power your music
JL Audio's JX400/4D 4-channel amplifier delivers 70 watts RMS to each of your car's front and rear speakers so you'll hear and feel your music clearly over the noises of the wind and road. You can also switch over to 2-channel mode, and power a pair of subwoofers with 200 watts RMS each, and fill your ride with bass.
Variable high- and low-pass filters allow you to tune the amplifier to match your particular speaker or subwoofer system. The amp includes speaker-level inputs, along with preamp inputs and outputs, so it's ready to work in virtually any system.
JL Audio designed this hefty little amplifier with sturdy, high-grade parts that ensure excellent heat management, provide high current flow, and deliver stable performance in almost any situation. Inside, you'll find oversized output transistors and a rugged MOSFET power supply; outside, the sleek, high-mass aluminum heatsink keeps things cool enough to virtually eliminate thermal shut-downs.
JX400/4D input and control panel
- 4-channel car amplifier
- 70 watts RMS x 4 at 4 ohms (100 watts RMS x 4 at 2 ohms)
- 200 watts RMS x 2 at 4 ohms
- Class D amplifier design
- frequency response: 20-20K Hz
- variable high- and low-pass filter (50-200 Hz, 12 dB/octave)
- preamp inputs and outputs
- speaker-level inputs
- wiring, fuse, and hardware not included with amplifier
- 4-gauge power and ground leads and a 40-amp fuse recommended
- 9"W x 2-3/16"H x 7-11/16"D
- warranty: 2 years
- Our 60-day money-back guarantee
- MFR # 99401
What's in the box:
- 4-Channel amplifier
- Two 10" speaker-level harnesses
- 2.5mm Allen wrench
- 4 Self-tapping screws (3/4" length)
- 4 Flat washers
- Owner's Manual
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More details on the JL Audio JX400/4D
Features & specs
|RMS Power Output (Watts x Channels)||
70 x 4 |
|Peak Power Output (Watts x Channels)||N/A|
|Power at 2 Ohms (Watts x Channels)||100 x 4|
|Bridged Power (Watts x Channels)||200 x 2|
|Minimum Impedance Bridged||4|
|Minimum Impedance Unbridged||2|
|Best Frequency Response||20-20k Hz|
|THD at Rated RMS Power||1%|
|Signal to Noise Ratio||93 dB|
|Low-Pass Crossover Frequency||50-200 Hz|
|Low-Pass Slope (dB/octave)||12 dB/oct|
|High-Pass Crossover Frequency||50-200 Hz|
|High-Pass Slope (dB/octave)||12 dB/oct|
|Bass Boost Frequency||N/A|
|Speaker Level Inputs||Harness (2)|
|Preamp Outputs||1 pair|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
Four-Channel Class D Amplifier: The JL Audio JX400/4D is a four-channel, full-range amplifier utilizing Class D technology. The JX400/4D can be operated with a wide variety of source units (aftermarket or factory) and system configurations (4-channel, 3-channel, or 2-channel).
MOSFET Switching Power Supply: The amplifier employs a rugged MOSFET power supply for outstanding reliability and operational stability.
- Rated Continuous
(RMS) Power @ 14.4V:
- 70 watts x 4 channels at 4Ω
- 100 watts x 4 channels at 2Ω
- 200 watts x 2 channels at 4Ω bridged
- Rated Continuous
(RMS) Power @ 12.5V:
- 50 watts x 4 channels at 4Ω
- 80 watts x 4 channels at 2Ω
- 160 watts x 2 channels at 4Ω bridged
Protection Circuitry: The JX400/4D's protection circuitry automatically shuts the amplifier down if thermal limits are exceeded, a short-circuit is detected in the speaker wiring, or if a dangerously low impedance is connected to the amplifier. Once the problem is corrected, the amplifier will return to normal operation.
Status Indicator Lights: There are two status indicator lights on the right side of the amplifier.
- Power (Green): This LED lights green to indicate that the amplifier is turned on and operating normally.
- Protect (Red): The Protection LED lights Red to indicate the amplifier's protection circuitry has been activated.
Input Sensitivity: The four-channel amplifier's Input Sensitivity Control is used to match your source unit's output voltage to the input stage of the amplifier for maximum clean output.
- Low-Level Input Range: 200mV-4V (RMS)
- High-Level Input Range: 2V-10V (RMS)
Input Mode: You can send four discrete channels of input into the amplifier, or feed all four channels with only two channels of input. The Input Mode switch has two positions: 4 Ch. for discrete 4 channels of input or 2 Ch. for feeding four channels with the inputs to Channels 1 & 2.
Variable Crossovers: The JX400/4D has a defeatable 12dB/octave filter for each channel bank. The crossovers can be configured as a low-pass or high-pass filter with a continuously variable cutoff frequency from 50 to 200 Hz.
- Filter Mode: The amplifier has independent 3-way switches that allow you to select either a Low Pass (LP), High Pass (HP) or Full-Range operation (Off) for Channels 1&2 and Channels 3&4.
- Filter Frequency: Separate rotary dials let you set the cutoff frequency between 50 to 200 Hz for each channel bank.
Power/Ground/Turn-On Terminals: The JX400/4D features set-screw terminals for the power, ground, and remote turn-on connections:
- Power and Ground: The set-screw Power and Ground connections are designed to accept up to 4 AWG wire. A 2.5mm Allen wrench is supplied for tightening/loosening connections.
- Remote Turn-On: The set-screw turn-on lead will accept 18 to 10 AWG wire. The same 2.5mm Allen wrench is supplied for making the connection.
Note: The Amplifier is not equipped with a fuse. An external 40-amp fuse (not included) must be installed on the power wire within 18" of the positive battery post. If a wiring kit is used which includes a fuse with a value other than 40-amps, the original should be replaced with a 40-amp fuse.
Speaker Output Terminals: The JX400/4D amplifier's eight set-screw speaker terminals will accept 16 to 8 AWG speaker wire. The amplifier's speaker terminals can be wired in a four-channel or bridged two-channel configuration. The 2.5mm Allen wrench is supplied for making connections.
Preamp Inputs: The amplifier features two sets of stereo RCA input jacks. The amplifier features a dedicated Input Sensitivity gain control for each pair of inputs. These controls are designed to match the input sensitivity of the JX400/4D to the specific signal source that is feeding it. The amplifier's low-level input can be set between 200mV-4V RMS.
Speaker Level Inputs: The JL Audio JX400/4D also accepts speaker level signals, including those from factory systems (without the need for a line-output converter), via the supplied supplied speaker-level harness. The head unit's speaker wires should be spliced to the speaker-level harness. The amplifier's high-level input can be set between 2V-10V RMS.
Preamp Outputs: The JX400/4D incorporates a pass-through preamp output sections, so that additional amplifiers can easily be connected to the same signal(s) feeding the amplifier. These preamp output signals are buffered to prevent noise and are always preamp level, regardless of the level of signals feeding the amplifier's inputs.
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