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The MOSFET power supplies in Rockford Fosgate's Punch 800.4 four-channel amplifier send power screaming to all the speakers in your system! At the same time, the combination of proprietary technology and clean circuit design give you a sparkling, detailed performance.

Built-in high-pass/low-pass crossovers let you tweak your tunes to work with your vehicle's natural acoustics. Punch Bass provides up to an awesome 18 dB of boost at 45 Hz for all the low-frequency slam you'd ever want.

If your receiver only has one set of preamp outputs, you can use the "4-2" switch to engage all four amp channels. And, if space is an issue for you, you can remove the endcaps to create a wider array of installation options.

Important Note: A 4-gauge amp wiring kit cannot be used alone to install this amplifier. Please call a Sales Advisor at 1-888-955-6000 for wiring recommendations.


  • 200 watts x 4 at 2 ohms
  • 400 watts x 2 in bridged mode
  • 2-, 3-, 4-channel or Tri-Way output
  • front and rear high-pass/low-pass crossovers (variable 50-210 Hz, 12 dB/octave)
  • MOSFET power supply and output devices
  • Maximum Efficiency Heat Sink Application (MEHSA) mounting technology increases the heat transfer from the MOSFET output devices to the heat sink, for higher power output, lower operating temperatures, and greater reliability
  • TOPAZ — noise-killing differential inputs that eliminate 80% of ground loop noise
  • Trans•ana circuitry keeps preamp voltages low and signal paths simple for outstanding audio quality
  • NOMAD — advanced protection circuitry for "intelligent" shutdown protection
  • speaker-level inputs
  • preamp outputs
  • Punch Bass boosts bass up to 18 dB at 45 Hz
  • 4-2 switch
  • 60-amp fuse and fuse holder required
  • dimensions: 18-7/16"W (14-7/8" without endcaps) x 2-7/16"H x 9-7/8"D
  • 3-year warranty

My system has plenty of power. Who needs an amp?

You might think you don't need an amp because you have a 400-watt system in your car, or because your new stereo puts out 50 watts a channel. But those are peak wattage ratings, which may boil down to 15 or 20 watts per channel, using the more realistic RMS rating. An amp sends your speakers the power they need to deliver your music with clarity and impact, whether you're using factory speakers or high-performance components. And low-frequency reproduction requires lots of power, so an amp is an absolute must if you're adding a sub to your system.

Rockford Fosgate Punch 800.4 Reviews

Hands-on research

What's in the box?

Download owner's manual

  • 4-Channel amplifier
  • RF center badge
  • 2 Speaker level input harnesses
  • Four 3/4" self-tapping screws
  • 12 set screws
  • One 7/64" Allen wrench
  • One 3/32" Allen wrench
  • Installation and Operation Manual
  • Punch Verification Certificate
  • "Team RF" sticker

Product Research

Inputs and Outputs
Wiring Recommendations


Manual Corrections


TRANSana (TRANSconductance Active Nodal Amplifier): TRANSana is a circuit that allows the audio signal to pass through the amplifier at low voltage. The signal is directly level-shifted to the fixed high voltage rails via a pair of drive transistors. Signal linearity is assured by an active node formed  by the drive transistors at ultrasonic frequencies. The result is crystal clear sound quality, even at high volume levels.

MEHSA (Maximum Efficiency Heat Sink Application): MEHSA is a Rockford Fosgate proprietary process that increases the heat transfer from the MOSFET devices to the heatsink. The multi-layer insulated metal MEHSA substrate operates with minimal thermal resistance, spreading heat both downward and outward to quickly dissipate heat from each device across the heatsink. This allows greater power output, enhanced thermal stability, and maximum reliability.

TOPAZ (Tracking Operation Pre-Amplifier Zone): TOPAZ is a circuit that simply eliminates noise. The TOPAZ circuit allows the amplifier ground to move with the source unit ground, creating a "noise elimination" zone just before the preamp section. If there is any noise in the ground coming down the RCA line to the amplifier, TOPAZ amazingly tracks it down and eliminates it. The result is a 30-40dB improvement of the isolation between input ground and chassis ground. 

DSM (Discrete Surface Mount): In the manufacturing process high speed robotics are used to place 0% tolerance resistors and large board traces providing greater reliability and efficiency.

NOMAD (NOn-Multiplying Advanced Decision): NOMAD is an intelligent protection circuit that uses an analog computer to make real time decisions regarding temperature, voltage, current and impedance. The unit is protected without limiting sound output unless needed.

Internal Crossovers: There are two  internal crossovers (one for the front and one for the rear) channels. Either crossover may be turned to Low pass, High pass or the crossover can be turned off for full-range output.

Crossover Frequency: The crossover frequency control is variable from 50Hz to 210Hz for either the front or rear crossover.  The slope of the crossovers is 12dB per octave.

RF Center Badge: Upon arrival, the RF center badge is not adhered to the amplifier. For installation flexibility, the badge can be rotated 180 degrees. Once you've decided in which direction the badge looks best for your installation, the peel-and-stick backing on the badge can be used to attach it to the amplifier.

Variable Punch Bass: Allows you to correct acoustical deficiencies by helping reproduce full range sound without adding excessive boost.  There are two controls (one for the front and one for the rear channels) which allow you to vary bass at a fixed 45Hz frequency by 0 dB to +18 dB.


Left Side Of Amplifier:

  • Two Crossover Switches : Allows you to select full range,  hi-pass or low-pass crossover operation at 12 dB/Oct.
  • Two Crossover Frequency Knobs: Allow you to continuously vary the crossover frequency for either crossover from 50Hz to 210Hz.
  • Front Gain: This variable gain control allows you to adjust the output level of the front channels
  • Rear Gain: This variable gain control allows you to adjust the output level of the rear channels
  • 4-2 Input switch: Allows the unit to be driven with either 1 or 2 pairs of inputs without requiring the use of "Y" connectors.
  • Punch Bass Knobs: Two knobs (one for the front and one for the rear channels) allow you to continuously vary bass boost centered at 45Hz by 0dB to +18dB. 

Inputs and Outputs

  • Input: Two pairs of Gold-plated RCA jacks (one for front and one for rear channels)
  • Output: One pair of Gold-plated RCA jacks (This is a full-range, pass-thru output) 
  • High Level Inputs:  Two Molex plug inputs for included harnesses
  • Speakers: Gold-plated set screw for four loudspeakers and accept wire sizes from 8 AWG to 18 AWG
  • GND (ground): Two gold-plated set screw terminals; each terminal will accept 8 gauge wire
  • B+ (power): Two gold-plated set screw terminals; each terminal will accept 8 gauge wire
  • REM (remote turn-on): Gold-plated 0.250" male quick-slide for remote turn-on lead. Note: A female quick-slide is not supplied.

Wiring Recommendations

Input, Power and Ground Wiring: This amplifier has two power and two ground inputs, and each input can accept 8 gauge wire. The amplifier wiring kits made to handle the current draw capabilities of this amplifier have 4 gauge wire, which is too large to fit the power and ground terminals. Since pre-packaged amplifier wiring kits cannot be used alone, you may purchase all the necessary items separately, or you may use a pre-packaged 4 gauge wiring kit along with two distribution blocks, 8 gauge power cable and 8 gauge ground cable. If you do not use a wiring kit with the necessary additional items, the separate parts and wiring needed to install this amplifier are as follows:

  • Two distribution blocks (each block should have one 4 gauge input and two 8 gauge outputs)
  • One fuse holder capable of accepting 4 gauge wire
  • One 60 amp fuse
  • Two power rings for 4 gauge cable
  • 4 gauge power cable (to connect the battery to a fuse holder and the fuse holder to a distribution block with a 4 gauge input)
  • 4 gauge ground cable (to connect a ground point to a distribution block with a 4 gauge input)
  • 8 gauge power cable (to connect the 8 gauge outputs of a distribution block to the two 8 gauge power inputs on the amplifier)
  • 8 gauge ground cable (to connect the 8 gauge outputs of a distribution block to the two 8 gauge ground inputs on the amplifier)
  • Remote turn-on cable (speaker wire can be used as remote turn-on cable)
  • One 0.25" female quick slide (to attach remote turn-on cable to amplifier)
  • One or two patch cables (depends on setting of 4-2 Input switch and/or the number of preamp outputs on the source unit)
  • Speaker wire


Dynamic Power Rating (measured at 14.4V):

  • Bridged Into A 4-Ohm Load: 525 watts x 2
  • Per Channel Into A 2-Ohm Load: 270 watts x 4
  • Per Channel Into A 4-Ohm Load: 150 watts x 4

Continuous Power Rating (measured at 13.8V):

  • Bridged Into A 4-Ohm Load: 400 watts x 2
  • Per Channel Into A 2-Ohm Load: 200 watts x 4
  • Per Channel Into A 4-Ohm Load: 100 watts x 4

Manual Corrections

Bandwidth Specification: The manual incorrectly lists the amplifier bandwidth as 10Hz-200Hz (+0.3dB); the actual bandwidth is 10Hz-200kHz (+3dB).

Included Wrenches: The manual incorrectly states that this unit comes with 9/64" and 3/32" allen wrenches; 7/64" and 3/32" allen wrenches are included with this unit.




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 verify what’s in the box, 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.