Alpine Authorized Online Dealer

Outstanding audio performance — you expect it when the amp is an Alpine. Alpine's V-Power amplifiers supply the high level of performance you want without shaking loose too much of your hard-earned cash.

The MRP-M850 mono amplifier will power your subwoofer with 500 watts of power. Add a second sub and the MRP-M850 pumps out 800 watts — enough power for some seriously "good vibrations." The variable low-pass filter adjusts the frequency output to match your system, while the Bass EQ lets you dial in some extra boost on the lows. A subsonic filter eliminates inaudible, ultra-low bass notes for cleaner output.

The amp's machined-metal heatsink keeps the internal parts cool and distortion low even when you're cranking the volume. Gold-plated screw terminals and RCA connections resist corrosion that can degrade signal performance.

Product Highlights:

  • mono subwoofer car amplifier
  • 500 watts RMS x 1 at 4 ohms (800 watts RMS x 1 at 2 ohms)
  • CEA-2006 compliant
  • variable low-pass filter (50-200 Hz, 24 dB/octave)
  • tuned Bass EQ (0-12 dB bass boost at 50 Hz)
  • subsonic filter (24 dB at 15 Hz)
  • MOSFET power supply
  • STAR Topology (minimizes internal noise and prevents ground interference)
  • gold-plated screw terminals
  • speaker- and preamp-level inputs
  • fuse rating: 25A x 3
  • 4-gauge amp wiring kit with 80-amp fuse recommended — wiring and hardware not included with amplifier
  • 15-5/8"W x 2-3/8"H x 9-9/16"D
  • warranty: 1 year
  • Our 60-day money-back guarantee

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.

Hands-on research

What's in the box?

Download owner's manual

  • Mono amplifier
  • Three 25 amp fuses (installed)
  • 7" Speaker-level input harness (8-pin Molex plug on one end and bare wires on the other)
  • 2 Terminal covers
  • 4 Self-tapping hex-head screws (M4 x 20mm)
  • 4 Machine screws for securing terminal covers (M3 x 12mm)
  • 3mm Allen wrench
  • 2.5mm Allen wrench
  • Owner's Manual (English/French/Spanish)
  • Customer Care Registration card

Product Research

Inputs and Outputs


Power Supply: The MRP-M850 amplifier's power supply uses MOSFETs to convert DC battery voltage to the higher DC voltages needed for high power. It supplies positive and negative voltages around 0V, rather than around 6V as with conventional single-polarity power supplies. The result is higher power levels and a dynamic range wider by as much as 10dB.

Low Pass Filter: The amp is equipped with a 50-200Hz variable low-pass filter with a slope of 24dB/octave. This being a mono subwoofer amp, the crossover is always engaged.

Subsonic Filter: This amp utilizes a 15Hz subsonic filter to eliminate super low frequencies that can rob power and damage speakers. The subsonic filter operates at all times, and cannot be turned off.

Bass EQ: The Bass EQ circuit provides a variable boost (0-12dB) at 50 Hz.

Inputs: The amplifier offers both line-level and speaker-level inputs for 2 channels. The supplied speaker-level input harness allows you to connect this amplifier to a receiver without preamp outputs; aftermarket or factory.

Terminal Covers: The amp comes with two plastic covers that protect and insulate the RCA, power, and speaker connections. Four supplied machine screws attach the covers to the amplifier.

Inputs and Outputs

Left Side Of Amplifier:

  • GND (ground): Gold-plated set screw terminal, accommodates bare wire up to 4 gauge
  • Battery: Gold-plated set screw terminal, accommodates bare wire up to 4 gauge
  • Remote: Gold-plated set screw terminal, accommodates bare wire up to 8 gauge
  • Speaker Output: Gold-plated set screw terminal, accommodates bare wire up to 8 gauge

Right Side Of Amplifier:

  • Line Inputs: 1 pair of gold-plated stereo RCA jacks
  • Speaker Level Input: Molex plug input for supplied 4-pin harness

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.

Alpine MRP-M850 Reviews

Average Customer Review:

7 reviews
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for future reference

Written By daniel, cumberland county, kentucky on Sunday, May 18, 2008

Crutchfield Customer Review (What's this?)

works good-- i'm a bells and whistles kinda guy and would like to see via a led or led's when the amp is producing peak rms amperage maybe in the future alpine will add the feature_ a test of time for the alpine will reveal its true preformance and value

Great Producte

Written By Mike, W Jefferson, OH on Sunday, April 27, 2008

I have the MRP-M650 currently in the trunk of my Grand Prix. Pushing 600
watts of power thru mono channel, just killing these Apline S12's. I've burnt
3 voice coils up in 3 different 2ohm subs. But i called Crutchfield and they
shipped me a brand new subwoofer no questions asked! Best amp I have
ever owned, an NO HEAT what so ever! My old 2 channel you could fry an
egg on it sometimes. I'm stickin' with Class D amps for my subs, I
recommend them to you as well.

Alpine MRP-M850

Written By daniel, Ogden, UT on Friday, April 04, 2008

The adjustable gain on all amplifiers is not meant for boosting the output of
the amplfier! Its purpose is so you can match the input votage of the rca's.
Example: If you where have 2 volt preouts on your deck, to do it correctly
you would adjust the gain to 2 volts on the amp. Now if you where to have
a deck with 4 volt preouts then you would adjust the gain to 4 volts on the

ALSO- Going over the rms is not a big deal AT ALL! For example I'm nearly
doubling the rms on my Alpine type S 5x7's which are 50 watts RMS and Im
powering them with 90 watts rms going to each speaker with a Alpine amp.
I turn my stereo all the way up, on a daily basis with full confidence that my
speakers wont blow because I KNOW my gain and crossover frequencies
are adjusted properly.

Alpine MRP-M850

Written By Andrew, so cal on Friday, February 22, 2008

Crutchfield Customer Review (What's this?)

I had the Alpine MRP-M650 install in my truck pushing 1 kicker Solo-Baric 10"l5 and you can hear it down the street. It has plenty of power!! Great buy

great amp

Written By wcmktb, USA on Monday, February 18, 2008

Crutchfield Customer Review (What's this?)

i have this amp wired at 2 ohms/800 rms to one 10 inch type r (supposed to be 500 rms...oops) in a ported MTX box...and i have to be very careful not to blow the sub! it uses the sub to its full potential! bass is clear with absolutely no distortion whatsoever and incredibly responsive. hopefully ill be upgrading the sub to 10 or 12 inch JL audio W7 so i can really see what this amp can do when the gain and bass eq are maxed out! i would certainly recommend this amp because it can power any sub 12 inch sub or less and rock it as hard as possible. NOTE- if going over rms on sub be super careful unless you wanna blow out!

Worth the Extra Money

Written By medic2580, Eastern Ky on Tuesday, September 04, 2007

I have this amp pushing 2 Alpine type r 10's. Wired for 2 ohms (400 per sub). This amp really pounds the subs. The sound quality is great. Almost knocks the subs out of the box and I only have the gain about half. Never gets hot. This amp is well worth the extra $ over some of the cheaper amps. Alpine is #1 when it comes to car audio. A++

Great amp

Written By thompsonm27, Woodward, OK on Saturday, July 21, 2007

Crutchfield Customer Review (What's this?)

I have this amp powering three JBL 10's with no problem at all. Plenty of power and does not even get hot.

Get everything you’ll need to enjoy your new Alpine MRP-M850

Bring the music from your amp to your speakers.
Patch cables take the music from your stereo to the amplifier. Most amp wiring kits don't include them.
Helps protect your car's charging system and improves power handling. Required power and ground wires not included with cap.
The right tools will make the installation easier.
Have your new amplifier put in by a qualified professional in your area.
T-Spec 12-gauge Speaker Wire

T-Spec 12-gauge Speaker Wire

Black/white jacket — priced per foot

Item #: 120SW12WB1


EFX 2-Channel RCA Patch Cables

EFX 2-Channel RCA Patch Cables

Core Series Twisted RCA patch cables — available in 5 different lengths (6-foot)

Item #: 142RCT6B


Add to Cart
EFX 2-Channel RCA Patch Cables

EFX 2-Channel RCA Patch Cables

Reference Series Multi-Core RCA patch cables — available in 5 different lengths (12-foot)

Item #: 142RR12


Add to Cart
EFX 2-Channel RCA Patch Cables

EFX 2-Channel RCA Patch Cables

Elite Series Braided Multi-Core RCA patch cables — available in 5 different lengths (3-foot)

Item #: 142RE3

Add to Cart
T-Spec 2-Channel RCA Patch Cables

T-Spec 2-Channel RCA Patch Cables

Available in 7 different lengths (10-foot)

Item #: 120RCA102


Add to Cart
T-Spec Capacitor

T-Spec Capacitor

1.5-farad capacitor with red LCD meter

Item #: 12015DDC


Add to Cart
S&G Tool Aid 87650

S&G Tool Aid 87650

Door Trim and Panel Removal Tool

Item #: 18187650


Skewdriver Pro SPK4042

Skewdriver Pro SPK4042

Ratcheting straight and offset screwdriver set with 40 bits (Skewdriver Pro with ratchet handle, pictured)

Item #: 180SPK4042


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S&G Wire Cutter/Stripper Tool

S&G Wire Cutter/Stripper Tool

Cuts and strips 12- to 22-gauge wire

Item #: 18119100


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Install Bay IB35400

Install Bay IB35400

Premium door panel and trim tool

Item #: 12035400

Add to Cart
InstallCard: Amp or Equalizer

InstallCard: Amp or Equalizer

Prepaid professional amplifier or EQ installation

Item #: 597421003


Add to Cart