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Rockford Fosgate Prime R400-4D

4-channel car amplifier — 75 watts RMS x 4

Save 50% on a select amp wiring kit with any $249+ car amplifier with any $249+ car amplifier
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Item# 575R4004D offer details

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Rockford Fosgate

Our take on the Rockford Fosgate Prime R400-4D

Rockford Fosgate packs more power per square inch into their Prime Class D amps than almost any other amplifier made, so you can put more music power in your vehicle's limited space. Your music will play loud and clear with one of these reliable and cool-running amps.

4-channel versatility
The R400-4D 4-channel amp puts out 75 watts RMS to each of your full-range speakers or components, giving them plenty of juice to rock. You can also use the front channels of the R400-4D for your front speakers while using the rear channels bridged to run a sub with up to 200 watts RMS. And, of course, you can bridge the amp to 2-channel mode to drive a pair of subs.

Clean power, extensive controls
Rockford Fosgate designed Prime amps to deliver Power Output Without Excessive Regulation (POWER), which means they'll respond quickly to the peak demands that you may throw at your system. High- and low-pass filters, along with Rockford Fosgate's famous Punch bass boost, let you tune your speakers for maximum performance, so your driver's seat will become your favorite place for listening.

Highlights:

  • 4-channel car amplifier
  • 75 watts RMS x 4 at 4 ohms (100 watts RMS x 4 at 2 ohms)
  • 200 watts RMS x 2 bridged output at 4 ohms (4-ohm stable in bridged mode)
  • CEA-2006 compliant
  • variable high- and low-pass filters (50-250 Hz, 12 dB/octave)
  • variable Punch EQ bass/treble boost (0-18 dB at 45 Hz and 12,000 Hz)
  • Class-D amplifier design
  • MOSFET power and output stages
  • frequency response: 20-20,000 Hz
  • preamp inputs and outputs
  • 4-gauge power and ground leads recommended — wiring and hardware not included with amplifier
  • no onboard fuses — when installing multiple amps in a system, an additional 40-amp in-line fuse between the distribution block and the amplifier is recommended
  • 9-1/8"W x 2"H x 7-3/8"D
  • warranty: 1 year
  • Our 60-day money-back guarantee
 

Hands-on research from the Crutchfield Labs (what are the Labs?)

Features and Specs

Features and Specs
Performance
RMS Power Output (Watts x Channels)
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75 x 4
Peak Power Output (Watts x Channels)
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---
Power at 2 Ohms (Watts x Channels)
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100 x 4
Bridged Power (Watts x Channels)
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200 x 2
Minimum Impedance Bridged
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4
Minimum Impedance Unbridged
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2
Best Frequency Response
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20-20k Hz
THD at Rated RMS Power
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1%
Signal to Noise Ratio
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90 dB
Input Voltage
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14.4v
Features
Amplifier Class
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D
Low-Pass Crossover Frequency
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50-250 Hz
Low-Pass Slope (dB/octave)
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12 dB/oct
High-Pass Crossover Frequency
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50-250 Hz
High-Pass Slope (dB/octave)
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12 dB/oct
Bass Boost
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0-18 dB
Bass Boost Frequency
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45 Hz
Fan Cooled
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No
Fuse Rating
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40
Speaker Level Inputs
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No
Preamp Outputs
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1 pair
Width (inches)
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9-1/8
Height (inches)
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2
Depth (inches)
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7-3/8
Parts Warranty
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1 Year
Labor Warranty
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1 Year

Product Research

Product Research
What's in the box?

Download owner's manual

  • 4-Channel amplifier
  • 3mm Hex key
  • Installation & Operation Manual
  • Amplifier Verification Certificate
  • 4 Self-tapping screws (length=1-5/8")

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team — they open the box, verify contents, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.

Features
Controls
Connections

Features

Overview: The Rockford Fosgate Prime R400-4D is a 4-channel full-range Class D amplifier. It is optimized to power a full-range front/rear speaker system. You can also bridge the front and/or rear channels to run a subwoofer or two. The Class D design is very efficient with a cast aluminum heatsink to keep it in a small footprint.

CEA 2006 Compliant: The R400-4D's power ratings are measured according to the strict standards dictated by the Consumer Electronics Association (CEA). These standards allow you to accurately compare the rated power output of all CEA 2006-compliant amplifiers, even different brands. Manufacturers who adhere to the standards can display the CEA 2006 logo on their products and packaging. The RMS power output is as follows (measured with a 14.4 volt input, <1% THD+N, 20 Hz-20 kHz):

  • 4-Ohm: 75 watts x 4
  • 2-Ohm: 100 watts x 4
  • Bridged (4-Ohm): 200 watts x 2

LED Indicator: The amplifier is equipped with a top-mounted LED indicator which illuminates blue when the unit is turned on. The LED illuminates red when a protection circuit engages (short circuit or too low an impedance is detected at the speaker connections). The amplifier automatically turns off if this occurs.

Mounting: The amplifier can be mounted vertically, horizontally, or inverted using the supplied mounting screws; horizontal mounting (right side up) will provide the best cooling.

Controls

Independent Controls: The R400-4D has independent, top-mounted controls for the front and rear channels. The controls include:

  • Gain Control: The amplifier has rotary gain controls (0 to 11) for front and rear channels.
  • Crossovers: The amplifier features independent Butterworth crossovers for the front and rear channels. Each crossover can be set for low-pass, high pass, or all-pass (full range). The crossover frequency is continuously variable from 50-250 Hz with a slope of 12 dB per octave.

Punch EQ: The rear channel has an independent Punch EQ (bass boost) control that works with the crossover switch. When the rear channel crossover is set to low-pass, the Punch EQ can add a bass boost, centered at 45 Hz, from 0 dB to +18 dB.

2/4 CH Switch: When the 2/4 CH switch is set to the 2 CH position, the inputs are switched to a 2-channel mode. The signal on the front input feeds all four output channels, however, you lose front to rear fading capability. In the 4 CH position, the amp uses both front and rear inputs and fading capability is restored.

Connections

Power Terminals: The power and ground terminals are nickel-plated set-screw terminals, and will accommodate up to 4-gauge wire. The set screws can be tightened/loosened with the supplied 3mm hex key.

Fuses: The amplifier does not have on-board fuses. A 40A fuse should be placed on the power wire within 18" of the battery.

Remote Turn-On Terminal: The remote turn-on terminal is a nickel-plated set-screw terminal that will accommodate up to 8-gauge wire. The set screws can be tightened/loosened with the supplied 3mm hex key.

Speaker Terminals: The speaker terminals are nickel-plated set-screw terminals that will accommodate up to 8-gauge wire. The set screws can be tightened/loosened with the supplied 3mm hex key.

RCA Input Jacks: There are two pairs of RCA input jacks for the front and rear channels. They are nickel-plated to resist signal degradation caused by corrosion.

RCA Pass-Thru Jacks: The nickel-plated RCA pass-thru jack provides a convenient source for daisy-chaining an additional amplifier without running an extra set of RCA cables from the front of the vehicle to the amplifier location.

 

Product Reviews

 

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Accessories

Things you'll need

Amplifier Wiring Kits
You'll need an amp wiring kit to install your new amplifier, as wiring is not included.
Rockford Fosgate RFK4
4-gauge amplifier power wiring kit
$114.99
In Stock
 
 
StreetWires ZeroNoise 3 ZN3Ki-04
4-gauge amplifier wiring kit with patch cable — red power/brown ground
$59.99
Out of Stock
 
 
Rockford Fosgate RFK4X
Complete 4-gauge amplifier wiring kit
Includes patch cable and speaker wire

Also available in:
Open Box: $143.99
$159.99
In Stock
 
 
EFX 4-gauge Amplifier Wiring Kit
Power and signal connections for your new amp
$79.99
In Stock
 
 
Kicker 09ZCK44 4-channel Amp Kit
Complete 4-gauge amplifier wiring kit — includes 4-channel patch cables and speaker wire
$169.99
In Stock
 
 
Kicker 09PK4
4-gauge amplifier power wiring kit
$129.99
In Stock
 
 
StreetWires ZeroNoise 5 ZN5K-04
4-gauge amplifier wiring kit — blue power/clear ground
$89.99
In Stock
 
 
Show more items
Speaker Wire
Bring the music from your amp to your speakers.
StreetWires 12-gauge Ultra Cable™ Speaker Wire
Blue/copper jacket — priced per foot
$1.00
In Stock
 
 
StreetWires 14-gauge Ultra Cable™ Speaker Wire
Blue/copper jacket — priced per foot
$0.75
In Stock
 
 
StreetWires 14-gauge Super Cable™ Speaker Wire
Translucent blue jacket — priced per foot (Clear)
$0.99
In Stock
 
 
StreetWires 16-gauge Super Cable™ Speaker Wire
Blue jacket — priced per foot
$0.40
In Stock
 
 
Stinger PRO Series 16-gauge Speaker Wire
Black jacket — priced per foot
$0.30
In Stock
 
 
Show more items
Stereo Patch Cables
Patch cables take the music from your stereo to the amplifier. Most amp wiring kits don't include them.
StreetWires ZeroNoise 3 Stereo Patch Cables
Available in two different lengths (19.7 feet)
$29.99
In Stock
 
 
StreetWires Zero Noise 5 Stereo Patch Cables
High-performance cables with superior noise rejection (16.4-foot)
$29.99
In Stock
 
 
StreetWires Zero Noise 7 Stereo Patch Cables
Available in 5 different lengths (16.4 feet)
$54.99
In Stock
 
 
StreetWires ZeroNoise® 9 Series 2-channel Patch Cables
High-performance cables with superior noise rejection (16.4 feet)
$109.99
In Stock
 
 
EFX 17-foot RCA Patch Cable
$8.99
In Stock
 
 
Show more items

Accessories we recommend

Firewall Bushings
If you have to drill a hole in your vehicle's firewall for your power cable, you'll need a bushing to protect the wire.
StreetWires FB4
4-gauge firewall bushing
$9.99
In Stock
 
 
Fuses
Get a spare fuse now so you won't be listening to silence later.
StreetWires AGU Type Glass Fuses
4-pack of fuses (50-amp)
$6.99
In Stock
 
 
Fuse Holders
For multi-amp systems, you'll need a separate fuse holder.
Rockford Fosgate RFFAGU Fuse Holder
Platinum-plated AGU fuse holder
Fits 4- or 8-gauge cable
$10.99
In Stock
 
 
EFX CAFH Fuse Holder
In-line AGU fuse holder accepts 4/8-gauge wire
$12.99
In Stock
 
 

Extras

Capacitors
Helps protect your car's charging system and improves power handling. Required power and ground wires not included with cap.
StreetWires ZeroNoise1 Capacitor
1-farad capacitor (16/20 volt) — Model ZN1-1FC
$99.99
In Stock
 
 
Tsunami Litewave Series PP92UM-CAP
2-farad canister-style capacitor
$149.99
In Stock
 
 
Tsunami LITEWAVE Series PP912UM-CAP
1.2-farad canister-style capacitor with blue LCD meter
$99.99
In Stock
 
 
Installation Tools
The right tools will make the installation easier.
Metra Crimp Tool and Connectors
Package contains crimp tool and over 150 pieces
$19.99
In Stock
 
 
S&G Tool Aid 87650
Door Trim and Panel Removal Tool
$9.99
In Stock
 
 
S&G Wire Cutter/Stripper Tool
Cuts and strips 12- to 22-gauge wire
$19.99
In Stock
 
After $10.00 Price Break
 
Pro.Fit Wire Worm
Installation tool helps route wiring through tight spaces
$12.99
In Stock
 
 
Bojo Trim Panel Tools
Set of 6 plastic tools — helps remove interior and exterior trim and door panels
$24.99
In Stock
 
 
DEI Heat Shrink Tubing
Black 4-foot length (Assortment)
$24.99
In Stock
 
 
Skewdriver Pro SPK4042
Ratcheting straight and offset screwdriver set with 40 bits (Skewdriver Pro with ratchet handle, pictured)
$49.99
In Stock
 
 
Show more items
Test Discs
Tune your system like a pro with Test CDs.
Autosound 2000 CD Set
$69.95
In Stock
 
 
Professional Installation
Have your new amplifier put in by a qualified professional in your area.
InstallCard: Amp or Equalizer
Prepaid professional amplifier or EQ installation
 
 
Add selected to cart
 

For a more in-depth review and enhanced detailed information on the Rockford Fosgate Prime R400-4D, please visit the Crutchfield website product page (/ISEO-rccbcspd/p_575R4004D/Rockford-Fosgate-Prime-R400-4D.html ).

Recommended Accessories See more accessories

Your featured item

Rockford Fosgate Prime R400-4D
Rockford Fosgate Prime R400-4D
4-channel car amplifier — 75 watts RMS x 4
$249.99
In Stock
 
After $10.00 Price Break
 

Amplifier Wiring Kits

Rockford Fosgate RFK4
4-gauge amplifier power wiring kit
 
$114.99
In Stock
 
 

Speaker Wire

StreetWires 12-gauge Ultra Cable™ Speaker Wire
Blue/copper jacket — priced per foot
$1.00
In Stock
 
 

Stereo Patch Cables

StreetWires ZeroNoise 3 Stereo Patch Cables
Available in two different lengths (19.7 feet)
$29.99
In Stock
 
 

Firewall Bushings

StreetWires FB4
4-gauge firewall bushing
$9.99
In Stock
 
 

Protect your gear with an extended warranty

Add 3 Year Warranty
Square Trade Warranty
$32.99
In Stock
 
 
 
Add selected to cart
 
Rockford Fosgate Prime R400-4D