JL Audio RD400/4 400 Watt 4 Channel Amplifier

JL Audio RD400/4 400 Watt 4 Channel Amplifier
Item #: RD400-4
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The JL Audio RD400/4 is a perfect amplifier for powering 4 speakers. The RD400/4 puts out 75 watts of RMS power at 4 ohms and 100 watts at 2 ohms making it a perfect match for most quality car speakers. This amp uses JL's NexD switching technology to deliver clean power with incredible efficiency and low distortion.

The RD400/4 comes in a stylish, black finish with control on the top of the amplifier underneath the protectie cover. This amp has 12dB/octave crossovers and high, low, and all pas filters. You have the option of running both high or low level inputs, the amp features automatic turn-on capability and has a selectable 2 or 4 channel input switch for the maximum installation flexibility. The RD400/4 has a 2-channel pre-amp output that allows you to easily add an additional amplifier to power more speaker or a subwoofer.

One of the unique features of the JL RD amplifiers is the LED clipping indicator. When you play test tunes, the amplifier will light up to first tell you when you get a clipped signal from your radio or head unit. This tells the volume level which you should never exceed. Once you know where your radio clips, you turn the gain up on the amplifier until you see the LED light up again. You turn the gain back slightly to make the light stop illuminating and you have gains perfectly set. This takes the guesswork out of the equation and ensures maximum power output without disotrtion and clipped signals.

Other Items You May Need:

  • 4 AWG Amp Wiring Kit
  • RCA Cables
  • Speaker Wire
  • JL Audio C2 Speakers

Product Specs
Class D
Output @ 4 Oms
75W x 4 RMS
Output @ 2 Ohms
100W x 4 RMS
4 Ohm Bridged Output
200W x 2 RMS
Frequency Response
12 Hz - 22 kHz
S/N Ratio Referred to 1 W
>84 dB (A-weighted, 20hz - 20kHz Noise Bandwidth)
THD+N @ Rated Power
<1% @ 2 Ohm Per Channel
Input Range
Switchable. Accepts Both High & Low Level Inputs
Minimum Power Wire Gauge
Fuse Rating
40 A (AFS,AGU or MaxiFuse)
Hi/Lo/All Pass Filters
Crossover Slope
12 dB/octave
Filter Frequency Range
50 Hz - 500 Hz
Infrasonic Filter
Remote Level Control
Channel Input Switch
Yes (2/4)
Pass Through Output
9.78"(W) x 6.96" (D) x 2.13" (H)

California Prop 65 Warning:
California Prop 65 Warning. Warning: Cancer and Reproductive Harm - www.P65Warnings.ca.gov


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