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Win the battle for great sound in your ride. Sound Ordnance amplifiers feature tough construction, rugged looks, and a 3-year warranty, so you can enjoy the full power of your music for the long haul. Even better, you can add Sound Ordnance to your arsenal at a surprisingly affordable price.

The Sound Ordnance M-4100 4-channel amplifier deploys 100 watts RMS to each channel, giving your music plenty of firepower. You can also bridge the amp to 2-channel mode to mobilize a pair of subs with 270 watts RMS each, or send 270 watts to a sub while the front channels run your full-range speakers. An adjustable high-pass filter makes sure your full-range speakers operate within their optimum range and give you the best tone possible. If you're driving a sub, the low-pass filter and variable bass boost allow you to control your bass barrage at will.

The M-4100 amplifier uses sophisticated power supply and output technologies to ensure clean amplification from the inputs all the way to your speakers. Special circuits protect the amp from overheating and short circuits, and a turn-on delay virtually eliminates that annoying thump when you turn your system on.

Product Highlights:

  • 4-channel car amplifier
  • 100 watts RMS x 4 at 4 ohms (135 watts RMS x 4 at 2 ohms)
  • 270 watts RMS x 2 bridged at 4 ohms (4-ohm stable bridged)
  • variable high-pass filter (15-250 Hz, 12 dB/octave)
  • variable low-pass filter (60-200Hz, 12 dB/octave)
  • variable bass boost (0-18 dB at 45 Hz)
  • PWM (pulse width modulation) power supply with MOSFET output
  • preamp inputs
  • fuse rating: 40A x 2
  • 4-gauge power and ground leads recommended — wiring and hardware not included with amplifier
  • 17-5/16"W x 2-1/8"H x 9-13/16"D
  • warranty: 3 years
  • 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.

Sound Ordnance™ M-4100 Reviews

Average Customer Review:

46 Reviews

Best bang for your buck!

Written by: Anonymous from San Diego, CA on October 5, 2014

Crutchfield Customer Review (What's this?)

This was my first full car stereo install and this amp was a perfect fit to power my speakers. This amp is what you need if you have a budget in mind.

Pros: Bang for your buck, can't beat it

Cons: It is a big amp.

Sound Ordnance™ M-4100

Written by: Anonymous from Kansas City, MO on July 19, 2014

Crutchfield Customer Review (What's this?)

So far so good. I have this paired with component Focal speakers. This thing has really gotten my music to new levels. Without it my hu would end up making my speakers distort at high volumes and now I'm able to get them to the point of ear bleeding without anything popping of cracking. Pure sound

Pros: Pretty easy to install. Great sound upgrade and easy to tweak for your preference.

Cons: As most every other review I've read about this. It gets pretty warm. Even in my hatch back with it mounted on the seat to get all that extra air when the windows are open

Great amp

Written by: Austin from Tucson, AZ on April 27, 2014

Crutchfield Customer Review (What's this?)

Great amp. Buy it


Cons: Gets very hot to touch

Great Amplifier

Written by: Steve from Charlotte, NC on April 11, 2014

Crutchfield Customer Review (What's this?)

Powerful amplifier with all the bells and whistles. Once adjusted, really brought my new Sony stereo and car to life.

Pros: Powerful, fully adjustable, low price,

Cons: The amplifier is a little larger than I expected but I still mounted it to the center of the rear seat in my 98 Volvo C70.

Great Amp

Written by: Shocker from Minnesota on March 28, 2014

Crutchfield Customer Review (What's this?)

This amp is great quality for a pretty decent price. I would recommend this to anyone looking for a good low priced option.



Sound Ordnance™ M-4100

Written by: Anonymous from 206 w. pine st. eagleriver wi 54521 on March 16, 2014

Crutchfield Customer Review (What's this?)

sounds fantastic would reccomend


Cons: none

4 way

Written by: Lenqt1 from Kansas City, MO on February 1, 2014

Crutchfield Customer Review (What's this?)

A little less bang for the buck than I expected.


Cons: Size

Sound ordinance m-4100

Written by: Blake from Redlands, ca on January 16, 2014

Crutchfield Customer Review (What's this?)

Excellent amp for the price, pair up perfectly with kicker 40cs 6.5 inch speakers. Replaced a polk pa660 and this amp is much better and half the price, I would highly recommend it

Pros: Great power, excellent sound, easy to use

Cons: Gets a little warm but if mounted in the open it's not a problem, many people had a problem with the mounting brackets but I found them to work fine

S/O M-4100

Written by: CHRIS C from MORGANTON NC on December 30, 2013

Crutchfield Customer Review (What's this?)



Cons: NONE

Fantastic amp for the price!

Written by: Love this amp! from Meridian ID on December 24, 2013

Crutchfield Customer Review (What's this?)

I'm running 2 prs of Kicker 6X9's in my Hyundai XG350L and this amp really pushes them great! The sound is clear and clean. Unbeatable power for the price. The amp does get somewhat hot but only when pushed really loud for a long time. Would buy another one and in fact am going to very soon as I am putting a system together for my semi truck.

Pros: Great power/low priced amp

Cons: None really

Great Amp

Written by: Chuck from Georgetown,SC on December 12, 2013

Crutchfield Customer Review (What's this?)

Just right for my Alpine Type R's.

Pros: Powerful

Cons: It gets a little hot

Sound Ordnance™ M-4100

Written by: MikeM from Indep., MO on November 3, 2013

I have had many amps and this one is a top 5. It has awesome power and clarity. I have been running mine for nearly 4 years now and it is still operating flawless. I am running a pair of components on the front channel while bridged on the other for a 10inch sub and it sounds great.

Pros: awesome power low cost

Cons: no cooling fan

Works great

Written by: Anonymous from Florida on October 23, 2013

Crutchfield Customer Review (What's this?)

The first one was a scratch and dent and had to be returned but the second one is very very good

Pros: Loud a lot of settings to tailor your sound

Cons: It gets warm

Awesome amp

Written by: Kyle from OK on October 21, 2013

Crutchfield Customer Review (What's this?)

Good quality. Clear sound.

Pros: Powerful, clear, reliable.

Cons: A little big.

sound ordnance

Written by: marquise from tracy ca on September 7, 2013

Crutchfield Customer Review (What's this?)

Best 4 channel amp I had in a long time sound quality is very clear took me awhile to learn how to adjust frequency easy to install and I will recommend this amp over alot of other amps

Pros: Great sound, easy to install, best amp so far

Cons: None

Great amp!!

Written by: Ben from Miami fl on September 6, 2013

Crutchfield Customer Review (What's this?)

This amp at the perfect time and installing it was easy. I have two pioneer 6x9's rear with 400w max and 5.25" pioneers in the front with 120w max. I have them hooked up to the amp and its connected to my pioneer hu. They sound amazing. The clarity and the power they produce it incredible. The amp sometimes gets a little warm but I live in Miami so it's like 90+ degrees outside. If you're considering buying this amp don't be hesitant. Go for it! You won't regret it.

Pros: Great sound. Never gets hot. Looks good.

Cons: It's a little bit heavier than other 4ch amps and a little bit bigger.


Written by: AndrewL from Houston, TX on August 18, 2013

Crutchfield Customer Review (What's this?)

Freaking rocks. Easy to install.

Pros: Ease of installation. LOUD

Cons: Power & Ground connections were too small to fit out of the box.

Sound Ordnance™ M-4100

Written by: Shawn from Stanardsville, va on August 6, 2013

Love it



Sound Ordnance™ M-4100

Written by: Anonymous from Brooklyn,New York on July 14, 2013

Crutchfield Customer Review (What's this?)

I purchased two Sound Ordnance Amps a M2250 which I returned cause it didnt have enough power for my subs. Also a M4100 so far I'm pleased with the M4100 my components were clear before with my alpine amps. But now with this amp there louder and crystal clear. Only bad thing right now is that its HUGE. It does get a little hot but nothing drastic. I'm waiting for another M4100 to be sent to me cause I returned the M2250 to use as a 2ch for my subs. Lets see how that goes.

Pros: Good for your components & speakers, has enough power

Cons: Its HUGE, gets a little hot but nothing drastic.


Written by: Eddie P from Pittsburgh, PA on June 30, 2013

So here it is. You want an amp that can consistently give power to your 100 watt (or lower) RMS speakers, while still supplying superior sound quality and reliability, without robbing $600 from you. You have it right here. This Sound Ordnance amp has made my Infinity Reference/Kappa set up in my '03 Eclipse one of the loudest and cleanest systems known to my friends and acquaintances. It is easily adjustable, and although rather large, it gets the job done, and it does it extremely well. I could turn off my sub, and my speakers could easily fulfill a similar position to it with some working with the receiver settings(I've tried it). However, I use this to push my higher notes and midrange, not the low ones (since my sub has an internal amp.) Needless to say, the high notes are so crisp and clear, at high volumes, passengers have claimed that their ears continue to ring for hours after exiting my car. This aspect pleases me, but I knew that was not the only thing backing my decision when I purchased this. This amp does tend to get very hot, esp. when used for extended time (like many). The vents, being on the bottom of the amp, meant I had to mount it upside down. As long as you somehow mount the vents to face up or outward, you should have no trouble. I even left this amp in full sunlight, 90 degree day, in my black car for about 8 hours, drove home, and it shut off because it knew it was hot. So even the fail-safe works. By the way, do yourself a favor. BUY THIS.

Pros: Lots of Power, Nice Look, Fail-Safe works, Easy Adjustment,

Cons: None on SOUND QUALITY, Can get Hot, Vents on Bottom,

Sound OrdnanceT M-4100

Written by: brett from Maryland on June 28, 2013

Crutchfield Customer Review (What's this?)

Great amp. No problems with hook up. God for powering speakers

Pros: Everything

Cons: Nothing

Awesome Amp

Written by: Elliott B from Fair Lawn, NJ on May 2, 2013

Crutchfield Customer Review (What's this?)

I love the amp its very good for the price you wont find anything that powerful, I did read the reviews before I bought it and I made sure that I put it in my trunk UNCOVERED because the biggest problem that everyone has seen with it is how ht it gets. All in all, if you install correctly and tune it properly you will have a great working amp for your system.


Cons: HEAT

Nice amp

Written by: Mike from Kyle TX on April 25, 2013

Crutchfield Customer Review (What's this?)

So far so good. They sound good, has crossover controls. Looks nice in the truck

Pros: Good sound

Cons: HEAVY! Sometimes the connectors don't always grab the wire.

I like it very much!

Written by: Rafael Siria from Los Angeles Ca on January 12, 2013

Crutchfield Customer Review (What's this?)

I like Sound OrdnanceT M-4100 because sound superior of my old amplifier.



Great amp

Written by: eyeless from ypsi, mi on January 7, 2013

Crutchfield Customer Review (What's this?)

I bought this amp to run my 4 infinity kappa 682.9cf speakers and it does a great job. No complaints yet

Pros: powers my 4 speakers with no problem

Cons: none

Not Impressed

Written by: Bruce from Suffield, CT on December 23, 2012

At first this amp seemed to sound and work well. After a few months, the amp started running real hot, to the point of shutting itself off. i was only driving the amp maybe 60% of its capability. I put up this because for the most part it worked and I only had to shut the system off for 5 minutes or so and turn it back on. After a year, a set of channels burned out, reducing the amp to 2 channel system.

Pros: Price

Cons: Instable, high heat, mediocre quality after a year burned out channels.

High quality at a fair price

Written by: BradC. from Santa Rosa, CA on December 19, 2012

Ok i wont lie this amp is HUGE, but in this case this is the ONLY part of the saying "you get what you pay for" i'm using this amp to power a set of Alpine SPR-60's and they are absolutely crystal clear! the other two channels are powering a pair of kicker Comp 8" subs which gives my truck a nicely balanced sound. the quality of this thing is great been using it for 3 months now without an issue!

Pros: EXTREME value, 3 year warranty, great sound quality even at extreme volumes

Cons: mounting feet are cheap plastic and hard to get tools in the holes, this thing is HUGE!

2 amps, 2 returns...

Written by: Byron from Michigan on December 11, 2012

I ordered this amp to power 2 sets of Polk MM6501 components. After dealing with the poor mounting design as others have mentioned, setting the gains (about 20% from lowest point), and crossover points(aprox 50hz hpf) I was initially impressed with the output from the amp. That was short lived though. After 30-40 mins of listening at fairly high volume there was a sudden introduction of distorted/muddy sound present. I shut the system down and checked the amp to find it extremely hot. Voltage was above 13 volts the entire time,with 4 gauge power and ground so I'm not sure why it was so hot. Let it cool for a few hours but it did not sound right still. Returned it and got another to replace it only to have a faulty channel on the 2nd unit. Sent it back and ordered a different brand this time. So much for the low buck install. Crutchfield did however handle both problems exactly as they should without giving me any hassle in replacing/exchanging the unit for another brand.

Pros: price

Cons: mounting tabs, high operating temp, & unreliable

Great Amp

Written by: Dave from Orange, Tx on September 30, 2012

Crutchfield Customer Review (What's this?)

Awesome amp. Powering a set of DXi 5250s in the front and a set of DXi525s in the rear doors of my truck. Plenty of power to drive wife insane. LOL. Only downside is the size of this monster. Only place I could put it was under the front passenger seat and it barely fits there. Thank goodness my wife is only 5'1". LOL 4 I gave 4 stars only because of its size.

Pros: Awesome power and ease of tuning. Multiple choices of use.

Cons: The size could be either narrower, shorter, or thinner. Just needs to be smaller.

S.O. M-4100 amp

Written by: Mike T from Palmyra, NJ on September 27, 2012

Crutchfield Customer Review (What's this?)

This amp not only looks cool but sounds amazing. Lots of EQ and very powerful. A bit long but under the seat so doesn't matter.



Crisp & Clean with ample power

Written by: Jackson from San Antonio, TX on September 26, 2012

Crutchfield Customer Review (What's this?)

Hooks up in a snap. Makes ample power at 4 ohms and doesn't seem to run super hot. I'll tip my hat to this product.

Pros: Simple installation

Cons: Manual does not describe or explain signal input level matching , main fuses were blown out of box. POOR SCORE HERE!

Great Budget Amp

Written by: HudsonA from Raleigh, NC on August 3, 2012

Crutchfield Customer Review (What's this?)

I bought this amp on the advice of one of the crutchfield specialists and I am very satisfied with it. Im powering two 100 watt RMS Alpine SPR-60's up front and a Kicker CVR-12 Sub rated at up to 400 watts RMS and it sounds great. As bridged the amp is rated at only 270 watts RMS I wasnt sure if the sub would be particularly loud but it is very loud and it sounds good as well with no distortion that i can tell. Though the amp is very large as some other reviewers have mentioned it fit perfectly on top of the sound ordnance sub enclosure i bought for the kicker sub so it takes up hardly any extra cargo space and makes all of the controls easily accessible as well. Only real downside to the amp so far (as I have yet to have a problem with heat like other reviewers given how my amp is mounted on top of the sub enclosure) is that the instructions in the manual for tuning the amp were far from descriptive and so it took me a while to get it tuned correctly (though im definitely no audio expert, perhaps others will have an easier time than I did). Overall, great amp for the price

Pros: Great amp for the price 3 year warranty

Cons: Manual was not very descriptive regarding how to tune the amp

Good for the price

Written by: Anonymous from East northport, new york on May 5, 2012

Crutchfield Customer Review (What's this?)

When i first got the amp i was surprised how nice it looked. I hooked it up and it made my alpine type r's sing. They sounded great! Crutchfields description says you can add a subwoofer by bridging two channels for 270 watts at 4ohms so i did that just temporarily until i get a seperate sub amp. But when you bridge the sub, it seems like i lost power to my interior speakers which kind of disappointed me. Im not 100% on that but it sounds like it. Also the amp gets extremely hot. I had to hook up some fans to it to keep it cool. But overall its a GREAT sounding amp. I would reccommend it.

Pros: Sounds great, looks great, even feels strong

Cons: Gets really hot

M4100- Awesome AM

Written by: Mike from Northern Kentucky on March 12, 2012

Crutchfield Customer Review (What's this?)

This amp has the power to virtually do anything. Supreme quality for a very reasonable price compared to some of the big named companies. I first bought an open box amp which was discounted and had to return it because it went out. Called customer support and they were awesome. They shipped out a new amp to replace it and a shipping label for the return with no difficulty whatsoever. Outstanding Customer Service. I will always but my home/car audio from this company.

Pros: Great look, Power, and versatility.

Cons: -Slightly large

Sound OrdnanceT M-4100

Written by: Animal from Fort Worth, TX on February 3, 2012

Crutchfield Customer Review (What's this?)

This amp rocks. I installed it in a 5th wheel RV as part of the 12 volt surround system. I'm running three sets of speakers. It doesn't get hot and it has all the power I need. Bill was also very helpful in helping pick out the right amp for my application.

Pros: Small enough, lot's of power and low heat emmision.

Cons: None

Good Bang For The Buck!!

Written by: KC from Sweet Home Alabama on February 1, 2012

Crutchfield Customer Review (What's this?)

I caught this on sale at Crutchfield, wanted something to go on two Kicker CVT shallow mount 10s under the back seat of my '05 F150 SCC. i figured if worse came to worse i could run it unbridged on the 4 door speakers. I'm very impressed with how well it drives the 10s, it's more then enough power (i've got it turned almost all the way down) and it runs cool mounted behind the rear seat (very cramped area with little ventilation)

Something not covered in the manual and nobody at Crutchfield seams to know either is that the amp has a switch for 2 or 4 ch input, nowhere does it tell you which 2 channels are for what. i called up Crutchfield and got a BS answer so i called back and got someone else, finely they had a supervisor call me and he tried very hard to find the answer but was never able to.

here's the break down, in 2ch input mode channels 1&2 are used to feed the amp and is HAS TO BE Mono (you can Y a single side of your patch cord if you don't have a mono output). if you use a stereo input (standard 2 patch cable) the phase difference will cancel out and the amp will produce low power.

my system doesn't provide a mono output so what i did was use stereo inputs with it on 4ch input and Y'd the inputs to channels 1/2 (right sub) and 3/4 (left sub).

Pros: I caught it on sale so it was good bang for the buck.

Cons: the plastic end caps for mounting. i read the reviews and knew what i was dealing with so i was careful not to over tighten the mounting screws. Crutchfield customer service let me down on the 2ch/4ch input question as mentioned above but it was the first time in 20+ yrs buying from them.

Sound Ordnance™ M-4100

Written by: CalmC from Alexandria, VA on October 9, 2011

Crutchfield Customer Review (What's this?)

The amp works well, it does require some searching to find a good place to stash it, but it fits almost perfectly under my rear seats so I don't lose any storage space to it. Only downside to it that I've noticed is a large parasitic draw when the car is off. With the amp connected the car draws 1.0 amps when off, 30 milliamps is about the most you want for a parasitic draw. With the amps inline fuse yanked the car draws about 5 milliamps, since it has no security system. Meaning that I have to yank the fuse or the battery is dead if I leave it sitting for more then a day.



Very Happy

Written by: Wayne from TN on October 6, 2011

Crutchfield Customer Review (What's this?)

Great amp at a great price. Works very well to run four 100watt Polk 6.5momos. Very easy install with great customer support. Crutchfield is awesome.



Sound Ordnance™ M-4100

Written by: Bryan R from Kingsport TN on October 4, 2011

Crutchfield Customer Review (What's this?)

This amp was very reasonably priced, It preformed much better than I expected!!!! Really brought speakers to life!



Good except for plastic & heat

Written by: stever761 from Spicewood, TX on June 24, 2011

Crutchfield Customer Review (What's this?)

I've had it in my truck for about 2 months now. I've been pretty satisfied with the performance so far. The footprint is hard to work with. Luckily I have a place under my rear seat in my Tundra DoubleCab. The length is very long for something you install in a vehicle and it generates a lot of heat. The vents are on the bottom and I've had issues on long trips where it overheats and shuts down. I flipped it over so that I now have the vents on top. The end caps where the mounts are located to secure the amp are plastic. I broke off both mounts on one end trying to secure it even though I had read the problems in other reviews and tried to be careful. The rest of this is pretty high quality, but that is one area where the ball was dropped. This is kind of heavy and in a major collision not having it secured properly could be a big hazard. Ditch the plastic chrome and use a metal mount that is incorporated in the amp chassis. I like the angled inputs to the wiring which makes it easier to access when you are trying to work in tight spaces with limited visibility. I also like that you use a philips screw instead of a flat head or allen wrench. The controls are easy to use, though the manual is lacking in more detail on the best ways to adjust them. It wasn't totally clear what each control did or how best to customize the sound. Performance-wise, I have no complaints. It puts out good clean sound.



2nd attempt

Written by: joshua from miami on April 18, 2011

Crutchfield Customer Review (What's this?)

At first the first one didn't work and was defective. Talked to a supervisor and him
along with a technical operator we had an rma sent out immediately. New one
works great. Only Con I have is the heat vents are at the bottom so if it does heat
up its are to have air escape when mounted. Power is clean and powerful. Thx for
all the help with this.



Sound Ordnance™ M-4100

Written by: Tom from St Paul, Mn on April 3, 2011

Crutchfield Customer Review (What's this?)

It's not as good as I expected it to be. I have it hooked up to 4x Kicker KS68 6x8's and they sound slightly better than if I had no amp. And the M4100 is poorly constructed with disposable plastic components. I know now I should have gotten a Kicker amp.



Sound Ordnance™ M-4100

Written by: Robert from Section,AL on January 26, 2011

Crutchfield Customer Review (What's this?)

I am very pleased with the Sound Ordnance M4100 amp. The quality is excellent and the
price is great.



Great amp but too big!

Written by: Fanaticny from Bay Shore, NY on December 11, 2010

Crutchfield Customer Review (What's this?)

This amp produces a good clear sound, I haven't fine tuned my setup yet but it already
sounds great. For its price and the amount of power it provides it's an excellent deal, if in a
budget get one of this bad boys asap. Amp didn't come with a manual, I'm not sure what
happened there. The only thing I didn't like about this amp is its size, it's just a bit too big!,
therefore 4 Stars.




Written by: kevin from Brockton, MA on July 17, 2010

Crutchfield Customer Review (What's this?)

Just recently bought this figuring out if i don't like it i can return it within 30 days so i thought id just give it a try. I have a kac-x40 (Kenwood excelon amp) and thats a 75x4rms this is a 100x4rms for cheaper so why not put it in powering Polk Audio db5251 components in the front and Kenwood KFC-6982IE 6x9s in the rear. Easy installation and when i was finished the thing was amazingly loud with less distortion then the kenwood my speakers definitely sound like their are suppose to right now and im not running any expensive power cable so its being under powered. Also doesn't look as good as it does in person it really does look great.



Very nice amplifier

Written by: Bryan from Louisville, KY on July 13, 2010

Crutchfield Customer Review (What's this?)

Bought a new eclipse amp from Crutchfield that needed to be returned. They made the return very easy and painless. Instead of replacing it, I decided to exchange it for this SO amp and I'm glad I did. The M-4100 sounds clean and powerful in my F-150. Installation was easy and the instructions were well written. I have it running a set of Rockford Fosgate component door speakers off the front channel and bridged to a RF 150W sub in the rear. We have had several days this month with temps in the mid 90's and this sub has not once shut down due to over-heating. The quality is equivalent to a much more expensive amp. And with a 3-year warranty how could I go wrong for this price?



Hands-on research

What's in the box?

Download owner's manual

  • 4-Channel amplifier with two 40A ATC blade fuses inserted
  • Spare 40A ATC blade fuse
  • 4 Self-tapping screws (5/8" length)
  • 4 Split lock washers
  • 4 Flat washers
  • Owner's Manual

Product Research



Power Ratings: The Sound Ordnance M-4100 is a four-channel Class AB amplifier with an RMS power rating of 100 watts per channel into 4 ohms, and 135 watts per channel into 2 ohms. The amp can also be bridged into a 4-ohm load for a power rating of 270 watts (x 2). Power ratings are measured with an input power of 14.4 volts.

Crossovers: The M-4100 is equipped with both high-pass and low-pass crossovers. The front channels (channels 1 and 2) and the rear channels (channels 3 and 4) have separate crossovers. You can set the low-pass cutoff frequency between 60Hz and 200Hz, and the high-pass cutoff frequency between 15Hz and 250Hz. Separate 3-way switches let you select low-pass, high-pass, or full range operation independently for the front and rear channels. The crossovers have a 12dB per octave slope.

Bass Boost: The amplifier has separate bass boost controls (labeled Bass EQ on the amp) for the front and rear channels. Each rotary control is continuously variable from 0dB to +18dB and boost is centered at 45 Hz.

LED Indicators: The M-4100 features two LED indicators: a green LED that illuminates when the amp is powered on, and a red LED that illuminates when the amplifier is in protect mode due to overheating or a short circuit in the speaker wire.


Removable End Caps: The end caps on the M-4100 are removable with a 3mm Allen wrench (not supplied) to make it easier to attach the power and speaker wires.

Power Connections: The power and ground connections are set screw terminals that will accommodate up to 4-gauge wire. (A 4-gauge amplifier wiring kit is recommended.) The remote turn-on terminal is a set screw terminal that will accept up to 8-gauge wire. A Phillips-head screwdriver (not supplied) is required to tighten/loosen the terminals.

Speaker Connections: The speaker connections are set screw terminals that will accommodate up to 8-gauge wire. A Phillips-head screwdriver (not supplied) is required to tighten/loosen the terminals.

RCA Inputs: The amplifier features two pairs of stereo RCA inputs for connecting your head unit--one pair for the front channels and one pair for the rear channels. If your head unit only has one pair of preamp outputs, you can feed all four amplifier channels with one pair of RCA plugs. (You will lose front-to-back fader capability if you connect the amplifier with one pair of RCA plugs.) The Input Mode switch allows you to select 4-channel or 2-channel inputs. The amplifier does not have preamp outputs.

Fuses: The M-4100 features two 40-amp ATC blade fuses.

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.

Product reviews from the Crutchfield Labs

Make your music sound lively and vital with a Sound Ordnance amplifier. Watch this Crutchfield video for a quick overview of what these amplifiers have to offer.

What are the Labs?

Customer Q&A

4 questions already asked

Thanks Ben just ordered it i was stuck between the 2 channel version of this amp but i want to push my speakers at its peak so i got the 4 channel! [ Rolando  Jul 29, 2014 ]
Actually I have this amp connected to two sets of Alpine Type R 6.5" Components. The amp does very well in pushing the speakers with no problems what so ever. [ WISTER  Jul 29, 2014 ]
I highly recommend this amp. I have it powering my 5.25" pioneers! It wouldn't be overpowered. The amp's output is 100w and your speakers have exactly 100w rms so it would be perfect. This amp reliable as well. Had it for almost a year and never gave me a problem. Good luck with your setup! [ BEN  Jul 28, 2014 ]
Not at all. Your speakers are rated at 100 watts RMS and this amp is putting out the same. For the price this is an excellent bang for your buck. If you want something high quality, I would look at the amps from either crescendo or hifonics. [ AUSTIN  Jul 28, 2014 ]
Thanks for your question. For information on selecting the best amp for your speakers I would recommend reaching out to an Advisor by phone (1-800-324-9695) or online chat. They will be able to help determine the differences between the amp models and help you make the best choice for your system. [ Greg  Jul 28, 2014 ]  Staff
I forwarded your question to an Advisor and they responded with the following: The answer is you can connect both or a combination of the two. The Sound Ordnance amp has both a high pass and a low pass filter. You can run it in 4 channel configuration or bridge the unit to run subwoofers. Typically you would either run 4 full range speakers to it, or connect two full range speakers to the front channels and bridge the two rear channels to connect a subwoofer. If you wanted to you could even bridge both the front and rear channels and just run subwoofers with it, although for that I would usually get a mono block amp instead of a 4 channel amp. If you would like to discuss further you can contact an Advisor directly by phone (1-800-324-9695) or online chat. [ Krissy  Mar 31, 2014 ]  Staff
Thanks for your question. For information on selecting the best amp for your subs I would recommend reaching out to an Advisor by phone (1-800-324-9695) or online chat. They will be able to help determine the differences between the amp models and help you make the best choice for your system. [ Jeff  Feb 01, 2014 ]  Staff
Overall the unit works well. During installation there was no fuse. Your company sent me one , but it wasn't correct. I had to search around to find one. [ MICHAEL A  Jan 20, 2014 ]
An AMP installation kit which will include the power cable from the battery and a ground cable. The kit will also include a RCA cable for head unit to amp along with a turn on power lead. I would also suggest a 2 farad capacitor to help keep power at the amp when hitting the hard bass notes. Outside of that, enjoy your amp, it is a nice unit for the price. You can't go wrong. [ Mrlittlejohn  Jan 19, 2014 ]
distribution block with fuses. thick guage wire for power and a good ground to eliminate noise. other than that you will need RCA cables to connect to the head unit. i am using it as a 4 channel amp (L+R and F+R). I love this amp, sounds great! [ MARTIN  Jan 19, 2014 ]
You don't really need anything to install this amp other than a screwdriver but make sure it's the pointy tip one because the screw are small. [ BEN  Jan 19, 2014 ]
I recommend at least 4 gauge power and ground cable. You haven't specified anything about what you're going to supply power to, so that's all you'll get outta me. [ AUSTIN  Jan 19, 2014 ]
Didn't really use any accessories for this. I got one of those amp kits that has the heavy gauge wires, fuse bock and fuse, patch cords, turn on lead wire, and the terminals. I made my own mounting platform for it [ MIKE  Jan 19, 2014 ]
its still in the box, the car it was going in got stolen [ BRENT A  Jan 19, 2014 ]
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. [ Krissy  Jan 19, 2014 ]  Staff