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Rockford Fosgate understands that the right amp is a crucial tool in the quest for ultimate sound — that's why they built the Punch 500X amplifier to rock the house! MOSFET power teams up with state-of-the-art technology to supercharge your vehicle's sound system with 62.5 watts RMS x 4 performance.

Built-in front and rear crossovers are switchable at 120 Hz (high-pass) or 80 Hz (low-pass) so you can configure the amp for a variety of tasks. Speaker- and preamp-level inputs, along with 8-gauge power and ground connectors, make it easy to integrate this amp into your system. If you're hurting for space, remove the amp's endcaps for a smaller profile.


  • 62.5 watts RMS x 4 at 4 ohms
  • 125 watts RMS x 4 at 2 ohms
  • 250 watts RMS x 2 at 4 ohms in bridged mode
  • requires 8-gauge power and ground leads — wiring and hardware not included with amplifier
  • 2-, 3-, or 4-channel output
  • Tri-way capable (Tri-Way crossover required)
  • front and rear switchable high-pass (120 Hz, 12 dB/octave) and low-pass (80 Hz, 12 dB/octave) crossovers
  • 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- and preamp-level inputs
  • dimensions: 13-7/16"W (9-15/16" without endcaps) x 2-7/16"H x 9-7/8"D
  • 2-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 500X Reviews

Hands-on research

What's in the box?

Download owner's manual

  • 4-Channel amplifier
  • RF center badge
  • Four 3/4" self-tapping screws
  • One 7/64" Allen wrench
  • One 3/32" Allen wrench
  • Twelve 3/32" set screws
  • 1 In-line 4/8 gauge fuse holder
  • One 50-amp AGU fuse
  • Two 9" speaker-level input harnesses
  • Installation and Operation Manual
  • Punch Verification Certificate
  • "Team RF" sticker

Product Research

Inputs and Outputs
Manual Correction


Cast Aluminum Heatsink: The cast aluminum heatsink dissipates heat generated by the amplifier's circuitry. The inherent advantage of casting provides a 30% improvement of cooling over conventional extrusion heatsink designs.

Trans-ANA (TRANSconductance Active Nodal Amplifier): The trans-ANA 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.

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. 

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.

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.

INDIGO (INDexed Ideal Gain Operation): INDIGO is a circuit that maximizes the output power of the amplifier by making better use of the power supplied by the car. As the battery voltage drops, INDIGO tightens up so the amplifier delivers the rated power, resulting in more consistent power coming from the amp.

Internal Crossover: The internal crossover is a 12dB/octave Butterworth filter selectable for 120Hz high-pass, full range, or 80Hz low-pass operation. The front and rear crossovers work independently.

RCA Pass-Thru Jacks: The pass-thru jacks provide 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. The pass-thru jacks output a full-range signal.

RF Center Badge: For installation flexibility, the RF center 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.


Right Side Of Amplifier:

  • Front Crossover Switch: allows you to select high-pass, full range, or low-pass crossover operation for front channels
  • Rear Crossover Switch: allows you to select high-pass, full range, or low-pass crossover operation for rear channels
  • 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 amplifier to be driven with either 1 pair or 2 pairs of preamp inputs without requiring the use of "Y" adapters

Inputs and Outputs

Right Side Of Amplifier:

  • Front Line Inputs: 1 pair gold-plated RCA jacks
  • Pass-Thru Line Outputs: 1 pair gold-plated RCA jacks
  • Rear Line Inputs: 1 pair gold-plated RCA jacks
  • Front High Level Input: Molex plug input for included harness
  • Rear High Level Input: Molex plug input for included harness

Left Side Of Amplifier:

  • Speakers: 4 pairs of gold-plated set screw terminals (LR, RR, LF, RF) that will accept up to 8 gauge speaker wire
  • GND: gold-plated set screw terminal that will accept up to 8 gauge ground wire
  • B+: gold-plated set screw terminal that will accept up to 8 gauge power wire
  • REM: gold-plated 0.250" male quick-slide for remote turn-on lead (Note: A female quick-slide is not supplied.)


Dynamic Power Rating (measured at 14.4V):

  • Bridged Into A 4-Ohm Load: 250 watts x 2
  • Per Channel Into A 2-Ohm Load: 125 watts x 4
  • Per Channel Into A 4-Ohm Load: 62.5 watts x 4


  • Without Endcaps: H=2.4375", D=9.875", W=9.75"
  • With Endcaps: H=2.4375", D=9.875",  W=13.375"

Manual Correction

Manual Correction: The manual incorrectly states the slope for the Butterworth 120Hz high-pass and 80Hz low-pass crossover is 24dB/octave. It is actually a 12dB/octave slope.

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.