I used Kickers 5 channel amp for 4 speakers and subs and I was happy with the quality. Can't remember the model number. It was in my old boat. I didn't need the loudest thing out there, but wanted to save space and used the 5 channel. I haven't tried the JL's.

As far as speakers I would give these a try. I installed two pair last year too see how they performed and I was pleasantly surprised. I will be replacing the rest of my speakers with them this summer. They also make a db691 which is a 6x9 that has some great reviews. http://m.ebay.com/itm/151487009533?nav=SEARCH. Not going to find a better price than that.

http://stores.ebay.com/Polk-Audio-Di...=p4634.c0.m322

Actually not true they are polk refurb's but if you understand how spkr's are refurbed then you know there new speaker's. Jl speaker's i have nothing but respect for they have managed to build quite a nice little spkr line sound very warm and rich but Polks for the money are amazing..As to amp's here's a little jewel i ran into... that well again is amazing it works just as stated..im sure harmon raided Crown for some tech input i cannot fathom how they can retail that amp for that money....Note one thing that's a sub amp read brute force that is all a sub need's not to much harmonic structure going on.....Have fun so many option's and so little time.


http://www.sonicelectronix.com/item_...FYGUfgodBFQAcQ

Now you guys really have me thinking…..

Amps do I need a marine grade amp. They will be housed in a water tight storage area. The boat is in salt water?

Being in salt water you need to have marine grade, the internal boards are sealed in epoxy. Corrosion carries current, its only a mater of time before it makes connection somewhere. Even though its in a compartment the salty environment will kill it. If you were in fresh water non marine components are fine. I have all standard car components and amps. speakers get soaked all the time, no problems in 4 years.
Remember, you get what you pay for! As long as you buy from an authorized dealer, good companies will stand by their products. Before you buy call the manufacturer and ask if the place you are buying from is authorized, most online retailers are not authorized by the factory = no warranty.