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Rockford Fosgate M400-4D thumbnail image
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5 star
79%
4 star
7%
3 star
14%
2 star
0%
1 star
0%



Durability
4.2
Value
4.8
Features
4.5
Design
4.8
Usability
4.8

Customer Reviews

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Rockford Fosgate Marine Amp

The following review is for a previous version (M600-4D).

Runs 600 watts to my cadence comp 6x9s
Beast set up

By $torm on June 11, 2013

35 found this helpful


Compact but Powerful

I bought this amp to put in a bass boat and I was very surprised when I opened the box. It's a very small amp and I had no problem mounting it where I wanted. It runs cool and powers my speakers with ease. My birth sheet said 507 watts.

By Jacob on March 17, 2014

34 found this helpful


Ole school

The ease of use and install, the look and design are awesome, the output is consistent and clear. I matched it with the rest of my Rockford Fosgate stereo. I am happy with it

By Ole school on September 19, 2013

30 found this helpful


Another home run!

The following review is for a previous version (M600-4D).

i have 3 of these in my boat. and they just flat out jam. its another great product from RF. i would recommend this to anyone with out hesitation or delay.

By Jay on January 17, 2013

28 found this helpful


this is a monster amp

The following review is for a previous version (M600-4D).

I have had this amp in the back of my chevy caprice, the trunk leaked and even with the water from the rain i never missed a beat. I would recomend besides rockford makes top notch equipment. I would recomend this amp to anyone whether boat leaky trunk or car looks great in a car as well.

By freddie on September 21, 2012

27 found this helpful


Great sound

The following review is for a previous version (M600-4D).

Have only had for a few weeks but so far everything works great. The sound is much better than my old Sony amp. Clearer sound especially at high volume. The amp has plenty of power for my small open boat even in wind and at 30mph. Instalation was easy. Had to install heavier wire and a bigger fuse.

By Clark on August 22, 2014

25 found this helpful


Giving it a second shot

The following review is for a previous version (M600-4D).

Received it from Sonic installed it and it sounded excellent. It's been 1 year and 2 months and now the unit stopped working. The unit powers on but there's no output to the speakers. I have it installed to a Clarion M502 and 4 Polk Audio MM6501. I'm giving it a second chance and ordering another since the sound quality was so good. I'm really hopping this one last a long time.

By Frank on May 20, 2014

25 found this helpful


Super Value!

The following review is for a previous version (M600-4D).

Bought the Amp a month ago and I am very satisfied with both Sonic and Rockford Fosgate. Did not rate high for durability since its a brand new item for me.

By Fernando on February 20, 2014

25 found this helpful


AWESOME!

This amp is AWESOME! Sounds great! Comes with a certification saying my serial unit was tested to 536 RMS. Would highly recommend.

By Randy on September 12, 2013

26 found this helpful


Good sound, small package

I have this amp pushing a pair of RF 262s and a pair of RF 282s. Much better sound than my previous MB Quart amp (and that one didn't sound bad either). Time will tell how it holds out - only 3 stars on durability because I have only had it for a few week no, but 0 issues.

By Gro on May 31, 2013

25 found this helpful


Second try

The following review is for a previous version (M600-4D).

I bought this product twice and the first one burnt up!! I reordered and the second unit works well but gets very hot!!!! Lots of air space around it!!! It will definitely crank out the sound!!! I have a all Rockford system the M1200 mono amp is great !!! 2 Rockford marine 10" subs 2 marine 8" and 2 marine 6.5 speakers !!! It sounds great!!!

By Mike on September 17, 2013

23 found this helpful


Great Sounding Amp

The following review is for a previous version (M600-4D).

Easy set up. Can run for a long time on a small battery. Does not get hot at all. Great sound have it hooked up to 2 sets of DC Gold speakers on a small (14ft) boat. Plenty loud even at 30 MPH.

By clark on February 16, 2015

21 found this helpful


Real Good Amp

It's my first marine amplifier. I used it whole summer. Can drive it at max without over heating. The longer period I used it is about three hours at maximum volume and the battery is still good for start the motor. Use it bridge with two eight inches Rockford Fosgate M282.

I Really think it's a quality amp and would buy it again.

By JayBee on October 31, 2012

22 found this helpful


Powerful amp.

Great amp. I have installed three of these and only had problems with one. I would recommend this amplifier.

By Coody Bug on February 2, 2020 Checkmark Icon Verified purchase

4 found this helpful


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