JL Audio JD400/4
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Item# 55823 / Condition:  Brand New    Review this product

JL Audio JD400/4

70 Watts x 4 @ 4 ohm / 100 Watts x 4 @ 2 ohm - 14.4V 4-channel Class D Full-Range Amplifier

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Save $50.00 | Reg. Price $279.99 In Stock
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Compact and Versatile


  • Fits nearly anywhere: 9.50 x 7.50 x 2.10 in. (242 x 190 x 53 mm)
  • Ultra-flexible outputs, capable of multiple configurations:
    • 4-Ch. Satellite Amp: power front and rear speakers with 75W x 4
    • 3-Ch. System Amp: power front speakers with 75W x 2 and a sub with up to 200W
    • 2-Ch. High-Power Satellite Amp: power 2pr. of speakers with 200W x 2
    • 2-Ch. High-Power Subwoofer Amp: drive two subwoofers with 200W x 2

NexDTM Switching Amplifier Technology


  • JL Audio's advanced high-speed switching technology delivers outstanding fidelity with very low noise and distortion.
  • Exceptional efficiency results in reduced current draw and heat, permitting reliable high power output within a very small chassis.
  • Full-bandwidth operation in all channels. (20 Hz - 20 kHz bandwidth)

Complete Signal Processing Sections


  • 12dB/octave high or low-pass filters for each channel pair, defeatable, with fully variable frequency selection from 50-500 Hz
  • Preamp outputs (buffered, pass-through type, from CH. 1&2)

Dual-Range, Differential-Balanced Inputs and Automatic Turn-On Capabilities


  • NO NOISE! Outstanding noise rejection prevents alternator whine and other noises.
  • Accepts line-level or speaker level signals up to 8V RMS, including those from factory systems, without a line-output converter
    • (LOC): just splice wires to a pair of RCA ends or RCA cables.
  • Selectable Input Mode switch permits one pair of inputs to feed both pairs of output channels.
  • Automatic turn-on option via Signal-Sensing or DC-Offset sensing

Integrated LED Clipping Indicators for Easy Setup


  • Simplifies input-sensitivity setting by providing accurate visual feedback of output clipping level.
    • Disconnect one speaker output wire
    • Play full-scale (0 dBfs) sine-wave through audio system, with head unit at 3/4 volume and tone controls set flat.
    • Adjust input sensitivity until light turns on, then back off slightly.
  • Separate, top-mounted LEDs report overall status and condition

4-Channel Class D Full-Range Amplifier, 100 W x 4 @ 2 Ω / 75 W x 4 @ 4 Ω - 14.4V

Utilizing JL Audio's exclusive NexD™ high-speed switching technologies, the JD400/4 amplifier is engineered to deliver loads of clean power, with excellent efficiency and low distortion. This little guy churns out 100 watts of audio from each of its four channels into 2 ohms (14.4V, 1% THD) and is fully bridgeable, so it can be used as a 3-channel amplifier, or as a 2-channel amplifier producing a whopping 200W x 2 into 4 ohms.

The JD400/4’s controls can be found on the input panel of the amplifier, with all speaker and power connections located along the opposite end of the extruded aluminum chassis. Signal processing features include high or low-pass 12 dB / octave filters (defeatable) for each channel pair, with continuously variable frequency selection from 50-500 Hz, and dual-range, differential-balanced inputs capable of accepting line-level or speaker-level signals. Automatic turn-on capability (via signal sensing or DC-offset sensing) is standard equipment.

Onboard LED-clipping indicators are also included surrounding each input sensitivity control. This convenient feature lets you set your amplifier’s input sensitivity, quickly and accurately, without special equipment. You will also find a set of buffered, pass-through preamp outputs on-board, so you can pass signals to another amplifier.

Rated Continuous (RMS) Power @ 14.4 V

  • @ 4 ohms: 75 W RMS x 4
  • @ 2 ohms: 100 W RMS x 4
  • Bridged @ 4ohms: 200 W RMS x 2

Rated Continuous (RMS) Power @ 12.5 V

  • @ 4 ohms: 60 W RMS x 4
  • @ 2 ohms: 90 W RMS x 4
  • Bridged @ 4ohms: 180 W RMS x 2

General Specifications

  • Frequency Response: 12 Hz - 22 kHz (+0, -1dB)
  • S/N Ratio, referred to highest rated power: >104 dB below rated power (A-weighted, 20 Hz - 20 kHz noise bandwidth)
  • S/N Ratio, referred to 1 W: >84 dB (A-weighted, 20 Hz - 20 kHz noise bandwidth)
  • Damping Factor @ 4 ohms: >150 / 50 Hz
  • Damping Factor @ 2 ohms: >75 / 50 Hz
  • THD+N @ Rated Power: <1% @ 2 ohms per Ch.
  • Input Voltage Range @ RCA Inputs: Switchable from 200 mV - 2 V RMS (Low) to 800 mV - 8 V RMS (High)
  • Min.Copper Power / Ground Wire Gauge: 4 AWG wire
  • Fuse Rating: 40 A (AFS, AGU or MaxiFuse™)

Signal Processing

  • Filter Mode(s): Low-Pass or High-Pass
  • Filter Slope(s): 12 dB/octave
  • Filter Frequency Range: 50 Hz - 500 Hz
  • Detented, Calibrated Filter Freq. Potentiometers: No
  • Filter Defeat Function: Yes
  • Remote Level Control: No
  • Remote Level Modes: N/A
  • Channel Input Mode Switch: Yes (2/4 ch.)
  • Pass-Through Preamp Output: Buffered
  • Source Channel Selection for PreOuts: No (always 2 Ch)

Physical Specifications

  • Height (H): 2.10 in / 53 mm
  • Width (W): 9.50 in / 242 mm
  • Depth (D): 7.50 in / 180 mm
  • UPC: 699440983617
  • Weight: 10
  • Authorized Internet Dealer
*Warranty: 1 Year Manufacturer warranty.
This item is accompanied by a manufacturer's warranty. If it is found to be defective, it may be returned to OnlineCarstereo.com for replacement within 1 year from the original date of purchase with proper return authorization.