JBL MA6004 4-Channel Full-Range Marine Amplifier

I purchased this bad boy to power my Igloo cooler stereo that I built for floating the local rivers and getting the parties started out in the sticks. I paired it with two JBL Marine 6x9s (bridged), and all I can say is that this thing is VERY loud and crystal clear with absolutely no distortion at high volumes. In fact, I think I may have gone a little overboard on my project - we brought the cooler out disperse camping the other weekend and it sounded like we were having a rave in the forest. Anyway, I digress. Back to the amp... I've seen a lot of reviews on here about overheating issues. Let me tell you, I ran this amp sitting inside of my cooler in the beating sun here in Sacramento with outside temps of over 95 degrees playing music at loud levels for hours with absolutely no issues whatsoever. Granted, the cooler may be insulating the amp a little bit from the temps, but still, I have no fans or other cooling devices inside. I haven't had a chance to test the marinized circuit board (and, quite frankly, I hope I don't run into a scenario where I'd need to, because that would mean my cooler was sinking), but the build quality on the amp is superb. It definitely looks like it could stand up the the harsh marine elements in a semi-exposed environment. This amp provides all of your typical adjustment knobs on the back: input gain, bass boost, high pass/low pass filter and frequency adjustment for both channels. The bass boost function works great, and really seems to add a lot of extra "umph" to my 6x9s. I've seen a few people posting general concerns about plugging a phone or other audio device directly into this amp using a 3.5mm headphone to RCA adapter (to avoid installing a deck). I can attest that you'll have absolutely no problem doing this with this amp; you will not need a pre-amp. The amp gets plenty loud using only the adapter cable. For those wanting to bridge 6x9s or other speakers, simply plug an extra RCA cable into the AUX output and then to the Rear input and plug your 3.5mm headphone to RCA adapter into the Front Input. A lot of you probably already know how to do this, but I figured I'd mention it for any newbies out there (like I was!) So, if you're looking for a LOUD, crisp, sexy looking amp that will keep your boat or other water toys rocking, this is the one for you. I've had it for a couple months now and it has performed flawlessly. Side note: This amp has three bright, blue power lights directly under the JBL logo. Something to consider if minor aesthetics are to be taken into account during your system build. UPDATE: June 2016 After two years, this amp is still kicking just fine. I've taken it out camping and floating over 20 times now and it sounds the same it did the day I bought it, and I've definitely put it through some abuse. All is not perfect, however. Some of the overheating issues that other buyers have mentioned have come to fruition. These overheating episodes only happen on very hot days when the amp is blasting at very high volumes. Since my amp is in an enclosed cooler, overheating is almost inevitable. I'm not going to knock any stars off my review; this is still an excellent buy and the sound quality cannot be beat. I plan on installing a pair of computer fans in the cooler to help cool this thing down when I really crank the volume on hot summer days.

I bought this amplifier to build a portable 2.1 system. The bridging features, crossovers, and independent gain controls are awesome and make a multichannel setup a breeze to hook up. Do note that if the front and rear channels are to receive the same signal, RCA jumpers from the pass through must be connected to the b channels externally. The three blue lights on the top are very bright. For size constrained projects, you might consider another product, so name sure you review the dimensions. Because I had the amp running off a small 12 volt agm sla battery, I was originally concerned with power consumption, and the amplifier gets quite warm. Although I originally attributed most of this to an inefficient design, the length of time the amp can run on such a small battery (18ah) has convinced me to look elsewhere for at least part of the heat build up. After thinking about it, I think that the fanless design, important for the marine grade build, may explain the issues some people have described. Most amplifiers with decent power output at least have vents, many with fans. This is a SEALED amplifier. It will get hot. Ensure proper and this amp works great. The features are nice, the price is right at ~ $100, and pungent l plenty of juice for most systems. I'm satisfied with this product, 4 stars because it won't work for everybody. Edit: lost a star because screw terminal stripped out way too easily

I'm by no means an expert on amps. I've only owned probably a half dozen of them over the years. This one seems to be a great amp for the money. I pushes four 7" marine speakers easily. Very loud and clear sound. No buzzing or engine noise. I've had some cheap marine amps that always had a slight buzz in the background. Better grounds, ground loop isolators, you name it wouldn't fix it. Not a problem with this one. No ground loop isolators, No super high end cables trying to get clean sound. Just hooked it up with some decent twisted RCA's to the head. Made sure it had a good ground and the proper sized hot wire for the length of the run. Sounds great.

Bought this Amp to power a stereo/cooler radio. It looks great, seemed to work great and was plenty of power to push the 5 speakers but for some reason the sub that it was pushing wouldn't work right. We tried a different sub that was working fine and it didn't work right either. Not sure what the problem was but at this point it was already installed and I paid a guy to install it, so it wasn't work taking it back out. It does push the four 5.5" speakers just fine and is loud and clear...good enough but not what I was expecting or wanting.

A great amp at a great price. I connected this amp to the bow thruster battery in my boat since its the most convenient location. Ran it for about four hours with the boat off and the AGM 100 amp hour battery had very little drain and could have gone for another 10. The amp is connected to two Bose 131 marine speakers and two JBL marine speakers. Even at close to full volume I could not hear any distortion. If you want an amazing amp that won't drain your boats battery then this is the one to buy.

I had this amp hooked up to 2 7"alpine marine speakers and the amp had plenty of power and a provided good sound quality. BUT it only lasted a couple months, had it mounted under my center console on my boat, and it must have gotten moisture on it, because it went haywire and now will not power back on. If you are looking for a amp for a boat and there is a possibility it could get wet, I would consider a higher quality product.

This JBL amp is a breeze to install and connect. The directions are fairly clear for those who are not familiar with wiring amps to head units and speakers. The low profile allowed me to install it in a tight space just forward of the port stowage on my Yamaha jet boat. I was able to drive two additional cockpit speakers, one 12" subwoofer, and two tower speakers with no problem. I'm contemplating buying another JBL amp and bridging the two for more output and additional speaker connections. At this price and functionality, it's well worth having two.

Worked great for 13 months... actually only in use for 6 of the 13. It was in a completely dry area with blower for ventilation so the elements shouldn't be the issue. We were listening on the water this past weekend and it just popped and no longer worked... Fusses looked good. Music wasn't even turned up... we were talking over the music so shouldn't have even been working hard. Flashing blue lights on the top indicate needs to be serviced or it's dead. For the price it'll be easier to replace than get serviced. I'll try another brand this time.