JL Audio M400/4
Crutchfield customer from Pinckney, MI on 9/21/2020
Sound is great. Replaced Polk Audio PA660's. The JL's are much better quality and sound. I'm looking to buy another in spring 2021.
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Defective
Crutchfield customer from Galt, CA on 9/13/2020
I must have gotten a defective amp. One of the speaker clips that compresses the speaker wire to hold it in kept falling off so I had to completely removed the amp to put it back in. The second time trying to tighten the speaker wire the clip fell out again. Without the clip there's no way to keep the speaker wire in place. Will be contacting Crutchfield to get a replacement or refund.
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0 of 0 found this helpful
JL Audio M400/4
Crutchfield customer from Rockaway, NJ on 8/11/2020
I installed this amp with 4 M3 speakers on my boat and the sound is awesome!
Pros: Great sound and easy install
Cons: none
0 of 0 found this helpful
Great Company
Crutchfield customer from Miami, FL on 8/2/2020
I'm fortune to have found such a great company that provides great products with exceptional customer service. Couldn't be more pleased. Thank you.
Pros: Product and Customer service
Cons: None
0 of 0 found this helpful
JL Audio M400/4
Crutchfield customer from Mukwonago, WI on 5/5/2020
Seems nice quality but have not yet installed. Expecting great things however hopefully my dreams become reality
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0 of 1 found this helpful
JL Audio M400/4
Crutchfield customer from Signal Mountain, TN on 8/12/2019
Great unit. Very impressed with the sound quality and build quality.
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0 of 0 found this helpful
JL Audio M400/4
Crutchfield customer from Angleton, TX on 7/13/2019
Just installed this along with 4 of their speakers. Loved the way you tuned the amp to the head unit
Pros: Quality product excellent sound
Cons: None
1 of 1 found this helpful
JL Audio M400/4
Crutchfield customer from Summerville, SC on 4/29/2019
This amp is awesome! I hooked up to JL 8.8's with this amp and it's sounds great and clear!
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JL Audio Marine Amps are the best in the business!!!
Brian from Murfreesboro, TN on 4/8/2019
Let me first off and say that Crutchfield is awesome!. I originally bought 2, Fusion marine amplifiers for my set-up. When I got them in the mail, I realized they were way more powerful than my Fusion 6" speakers could handle. Talked with Crutchfield and explained my situation and requirements. No problem, they emailed me a return label within minutes and by the end of the day, they went ahead and sent me 2 of these amps. Customer service is outstanding!!! I installed these amps. Each amp is powering 4 Fusion MS-FR6022 speakers. I will tell you the sound quality is amazing. These amps push my speakers nice and loud, with no distortion. I blasted my music for hours and still had plenty of battery left over. Prior to my system redo, I had 2 Rockford Fosgate M400-4D (which I did not buy from here) and they were garbage. Within months, both of them started to have channels go out. Sound quality diminished. I cannot even begin to tell you the difference between Rockford Fosgate and JL Audio. Yes, you will pay for the Jl Audios, but save yourself a ton of problems and headaches in the future. I have no doubt that if I have any problem with these amps, between Crutchfield and JL Audio, it will be taken care of. Thank you again
Pros: Everything
Cons: Nothing
2 of 2 found this helpful
Great Product...DUH ITS JL!
Andrew from Lexington, SC on 9/1/2018
Big things definitely come in small packages when it comes to this M400/4. I'm powering 4 JL M7.7's on my side by side and this amp rocks those speakers and has handled att the abuse of the trails and mud. I will most definitely be purchasing another in the future for the wife's rig.
Pros: Love the compact size of this amp. Great power and easily adjustable.
Cons: I wish it had the pig tail like it little brother the M280/4
0 of 0 found this helpful
Can't be Topped for Marine Application
John from Orange, CT on 8/31/2018
Clearest Amp I have ever owned! I have never skimped on my amps but this Marine amp is the best I have ever heard teamed with JL speakers, Blows my old Wetsounds system away.
Pros: Huge output at a low voltage input. Construction Quality is great, very impressive. Plainly explained, well illustrated directions.
Cons: You get what you pay for, do it one cry once and enjoy the best for life!
0 of 0 found this helpful
JL Audio M400/4
Michael from Ste Genevieve, MO on 5/30/2018
Very powerful and compact. Easy to install! I replaced my old M4300's with 2 new technology M400/4's
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0 of 1 found this helpful
Plenty of power
Brad from Canyon Lake, TX on 5/27/2018
JL quality. Compact and performs well. Paired with M700/5 with remote bass control. Marine rating definitely needed for the boat. Powering 4 tower speakers bridges off the M400/4. Have to turn down the gain, they are so loud!
Pros: Compact and quality
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2 of 3 found this helpful
JL Audio M400/4
Crutchfield customer from Wimberley, TX on 5/21/2018
Nice Amp sounds good, best of all has a small footprint for boat mounting
Pros: Small size,with plenty of power
Cons: Not waterproof
0 of 1 found this helpful
JL Audio M400/4
Les C from Prior Lake, MN on 5/20/2018
Small, compact, powerful, good design
Pros: Small and compact but still has all the power you need
Cons: None
0 of 1 found this helpful
Great sound through all volume ranges
Doug from Petaluma, CA on 4/12/2018
I bought the JL Audio M400/4 amp for my 2017 Harley Davidson Road king with a full fairing, I replaced a Rockford Fosgate PBR300/4Amp that was clipping and I was not happy with it's performance. Memo a sales associate with Crutchfield recommended it to me. I rewired the complete radio system with my new amp, It performs beautifully at all volume ranges. It is truly worth the time and money to use this amp. If you want a great sound I highly recommend this for your Harley.
Pros: Outstanding performance clean installation WOW!
Cons: None!
1 of 2 found this helpful
Powerful little amp.
Bill from Chambersburg, PA on 7/9/2017
This a smokin little amp ! Incredibly small yet powerful, very flexible in the way amp can be set up. Clean detailed music when matched to quality speakers like JL MX series marine. Amp seems expensive but worth the price in terms of quality and music reproduction.
Pros: Sound quality and flexibility.
Cons: None
0 of 1 found this helpful
JL Audio M400/4
Stephen from Taylorsville, NC on 7/5/2017
Only had my new system a week but WOW, sounds great. JL is a leader in marine sound technology and the best part ,made in USA. I'm going to add their 8'' subwoffer to my system.
Pros: Extremely well made and out performs my expectation .
Cons: None
1 of 1 found this helpful
JL Audio M400/4 INCREDIBLE CLARITY
Joe from Lenoir city, TN on 3/6/2016
Easy installation, the unit will handle just about any input signal including line out from the stereo unit. The wire terminations are very secure and solid all included tools (allen wrench) are provided to terminate wires and secure them. Great clarity and very easy to set up for all audio sources, as long as you have a multi-meter to read the AC voltage.
Pros: Easy of installation Easy to configure Very well thought out design
Cons: None so far but had the unit only a couple of weeks.
1 of 1 found this helpful
Great amp for rzr1000 xp4
Crutchfield customer from Scottsdale, az on 5/16/2015
Great amp for my rzr. Small with lots of power. Easy to install
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3 of 3 found this helpful
Outstanding couldn't be happier
Fourwinns from Wichita Falls TX on 4/17/2015
I bought this item as scratch and dent.. I couldn't find a scratch not dent on the amp. Wired 4 JL MX650's to my head unit first and was disappointed (obviously) then plugged in the speaker wire I had run for the amp. 100x better clearer and LOUD! I probably have the perfect amp for those particular four speakers but the difference was incredible, not to mention the sound is amazing. I highly recommend ALL JL AUDIO MARINE products they're in my opinion the best you can get.
Pros: Good power, no noise, great sound
Cons: Haven't found any cons so far
2 of 2 found this helpful
Awesome tiny-mite!
Chris from Katy, TX on 3/13/2014
Powering two jl 7.7 coax's and two channels bridged to power the 10" open baffle sub in our little ski boat and it plays detailed, soft and load, and it puts out clean undistorted full range watts!
Pros: Small easy to hide
Cons: Forget it's there!
2 of 2 found this helpful
M400/4 amp
Oz from Frankfort, Ky. on 9/8/2012
Installed JL amp for my boat , sounds great and after 5 hours of playing music, the amp wasn`t hot. Will tell family and friends.
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3 of 3 found this helpful