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Alpine MRX-M240

X-Power Series mono subwoofer amplifier — 2,400 watts RMS x 1 at 2 ohms

6 Reviews | 1 question - 1 answer

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Item # 500MRXM240

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Our take on the Alpine MRX-M240

Alpine's X-Power MRX-M240 mono amplifier uses the latest amp technology to play your music loud and clean without taking up much space. And this amp employs some of the same circuitry developed for Alpine's top-of-the-line PDX digital amps, so it'll bring exceptional sound to almost any ride.

Alpine Authorized Online Dealer

Digital technology that sounds perfect

Alpine's X-Power MRX-M240 mono amplifier uses the latest amp technology to play your music loud and clean without taking up much space. And this amp employs some of the same circuitry developed for Alpine's top-of-the-line PDX digital amps, so it'll bring exceptional sound to almost any ride.

Massive power for high-level systems

The MRX-M240 puts out up to an astonishing 2,400 watts RMS to your subwoofer system, perfect for competitors and true bassheads. And it'll operate safely with a 1-ohm load, making it useful in a variety of sub system installations. Onboard low-pass and subsonic filters let you get the best sound out of your setup, while a parametric bass boost helps to fatten up the sound at exactly the right notes, if you need it.

Looks cool too

A power management system optimizes the amp's performance and keeps the music playing, even when you're pushing it hot and hard for a long time. Speaker-level inputs with an automatic turn-on feature simplify system hook-up.

MRX-M240 control panel

Confused about impedance? Check out our article on matching subs and amps.

Product Highlights:

  • mono subwoofer car amplifier
  • 1,500 watts RMS x 1 at 4 ohms (2,400 watts RMS x 1 at 2 ohms)
  • 1,000 watts RMS x 1 at 1 ohm
  • CEA-2006 compliant
  • variable low-pass filter (50-400 Hz, 24 dB/octave)
  • variable bass boost (0-12 dB at 30-80 Hz)
  • variable subsonic filter (5-30 Hz, 24 dB/octave)
  • optional remote level control (RUX-KNOB)
  • Class D amp with MOSFET power supply
  • preamp and speaker-level inputs
  • preamp outputs
  • fuse rating: 175A x 1
  • 1/0-gauge power and ground leads recommended — wiring and hardware not included with amplifier
  • 18-1/8"W x 2-5/16"H x 9-1/16"D
  • warranty: 1 year
  • Our 60-day money-back guarantee

What's in the Box:

  • Mono amplifier with a 175A Mega fuse installed
  • Left plastic terminal cover
  • Right plastic terminal cover
  • 4 Terminal cover screws (M3 x 10mm)
  • 4 Self-tapping screws (M4 x 20mm)
  • 2.5mm Allen wrench
  • 5mm Allen wrench
  • 7" Speaker-level input harness
  • Owner's Manual (Eng/ Fren/ Span)
  • Warranty sheet
  • Online registration card
  • Alpine Verification Certificate

Featured Video:

I love it. It has a lot of power for being small and light.

ededdy55, St. Paul,MN


Alpine MRX-M240 Reviews

Average Customer Review(s):

(6 Reviews)

Good amp til it just quit working

Doug from Ladson, SC on 5/24/2017

Bought this to pair with 2 alpine type r 10's worked very well for bout 6 mo ths then i let sit while back overseas for 9 months came home and found did work anymore , blue light would light up but nothing . Had professional audio place test everything from battery back and they even ohm tested system said even though everything was hooked up correctly that for some reason amp isnt working, took back off can not find nothing burnt or damaged and even check 175 mega fuse on side all looks good , im puzzled as to why amp will not work ?????

Pros: Worked well for short period then just stopped working



ededdy55 from St. Paul,MN on 9/25/2014

Crutchfield Customer Review (What's this?)

I love it. It has a lot of power for being small and light.

Pros: As I wrote, small, powerful and light weight.

Cons: 0000000000000000000000

Alpine MRX-M240

Kevin K from Madison, WI on 9/7/2014

Crutchfield Customer Review (What's this?)

Honestly I think everyone knows that Alpine makes awesome amplifiers. I have a Cadillac STS with (2) Orion 12" HCCA Competition dual 4 ohm 2000 watt RMS 4000 watt peak subwoofers each with their own MRX-M240 running at 2 ohms at the moment. I also have had them pound many other different subs out there, but when you see these speakers with their 445 ounce magnets being easily powered by these amps I am sure it would make you a believer! One certificate rates the amp at 2760 watts at 2 ohms and the other amp's certificate tested in at 2956 watts at 2 ohms. I mean these speakers are literally almost 70lbs each and absolutely demand and need a ton of power to perform and these amps do it with ease. I have 100% confidence these amps can power any sub out there. So if you want real, serious power here you go....for a very good price. Honestly I can't imagine having any more power as I have yet to meet someone that can actually crank this system and actually endure it for more than a couple minutes because of the extreme pain in your ears- so do you really need any more power? I think that basically sums it up, this amp is POWERFUL and can do the job.

Pros: best of the best

Cons: none

Alpine MRX-M240

Anonymous from South Bend, IN on 5/26/2014

Crutchfield Customer Review (What's this?)

Got a great deal on this not to mention a lot of power.

Pros: Loud!!!

Cons: None....

Alpine mrx m240

Pacman from Wasilla ,Ak on 8/9/2013

This amp is a beast!!! I have it on 4 t1 12s @ 2 ohms and ?????? .... Getting 157.6 dbs

Pros: Tons of power & versatile ohm loads with 1 ohm being 1000 rms and 2 being 2400. My sheet rates mine @ 2606@ 2 ohm.

Cons: This thing is power hungry. Do not buy this amp if you don't have your big 3 and @ least 3 deep cell batteries with your h.o alternator

best ive ever had

mrboombastic from ventura California on 9/29/2012

I have the alpine mrx m240 paired with two alpine type X's that 3000 watts each ...if your looking for something that handle any subs you throw at it ..this is the amp there is so much power that i fear to turn it up all the way it makes you feel like your in a tornado it really gets your blood pumping if you have the money spend it you won't be disappointed

Pros: Can handle any subs you throw at it

Cons: Requires alot of power and tends to make your headlights flicker


Hands-on research

Product Research



MRX Amplifier Design: Class-D amplifiers boast higher efficiency, produce less heat, and draw less current than traditional Class-AB amps. The MRX series benefits from the technology trickledown from Alpine's more expensive PDX amps, including Direct FET final outputs, thermal management processor, 6-Layer Glass Epoxy PC Board; combining to create a high-end sound quality without the bulky heat sinks required by most amps in this power class.

STAR Topology: Alpine's unique STAR (Signal Transit for Accurate Response) Circuit PCB design provides a single common ground for all amp sub-blocks, preventing ground interference and minimizing internal noise.

Power Management Processor: The multi-stage Power Management Processor continuously monitors component temperatures throughout the amplifier and decreases power output if anything gets too hot. When playing music under heavy loads for long periods, the circuit automatically reduces power output slightly at first, and then further in a second stage if necessary. This two stage approach provides an interruption free listening experience.

CEA 2006 Compliant: The MRX-M240's power ratings are measured according to the Consumer Electronics Association CEA-2006 standards. 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 power output is measured from 20 Hz to 400 Hz using a 14.4 volt power supply with no more than 0.01% THD+N:

  • 4-ohm: 1500 watts
  • 2-ohm: 2400 watts
  • 1-ohm: 1000 watts

Signal-to-Noise: When measured under CEA-2006 conditions (reference 1 watt into a 4-ohm load) the signal to noise ratio is 82 dBA. Measured at the rated power output S/N is 108 dB.

Verification Certificate: The amplifier comes with a certificate that lists the RMS power output measured from that specific amplifier. It also lists the model number, serial number, test date, and the test conditions (voltage and impedance).

Auto Turn On: When using the speaker level inputs the X-Power amplifiers automatically turn on when voltage is detected on the signal inputs, making them an easy factory system upgrade.

Low Output Impedance: With low output impedance, the MRX-M240 outputs tightly controlled bass, with a damping Factor rated at greater than 1000.

LED: The top panel LED power indicator glows blue when the amplifier is turned on.


Gain: The MRX-M240's gain is set according to the level of the incoming signal. The line-level input gain setting is continuously variable from 100 mV to 4.0V; the speaker-level input gain setting is continuously variable from 250 mV to 10.0V.

Crossover: The low-pass crossover point is continuously variable from 50 to 400 Hz and the slope is 24 dB/oct; the crossover cannot be bypassed.

Subsonic Filter: The amp also has a 24 dB/oct subsonic filter, continuously variable from 5 to 30 Hz.

Bass EQ: Bass boost can be applied to the subwoofer output; it's variable from 0 to +12 dB with a variable center frequency of 30-80Hz.


Power/Ground/Remote: The MRX-M240 features set-screw terminals for the Power, Ground and Remote Turn-on inputs. The Power and Ground terminals will accommodate up to 1/0 gauge wire, and the Remote Turn-on terminal will accept up to 8 gauge wire.

Speaker Output: The speaker outputs terminal is also set-screw terminals and will accept up to 8 gauge wire.

Line Input/Output: Line level RCA is the preferred input connection. The full range stereo line output allows easily adding another amp without running a second set of cables.

Speaker Level Input: Use the included speaker level input harnesses if the connected radio has no preamp outputs.

Fuses: The amp is protected by a chassis-mounted 175-amp Mega fuse.

Remote Bass Control (optional): Alpine's RUXKNOB wired remote (sold separately), connects to the amp's RJ-25 Remote Bass Control jack, and offers control of the subwoofer output level from the front of your vehicle. The linear attenuation can be adjusted from 0 to -20dB.

Our Product Research Team

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Q & A

Customer Q&A

1 question already asked

For details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle. [ Greg  May 02, 2014 ]  Staff