The amp has an ohm stability. say a particular amp is 2 ohm stable. now your speakers and how you wire them determines the actual ohm load on the amp. So you are using an amp with a 2 ohm stable channel. your speaker is rated at 4 ohms. So you are running 4 ohms. Now you decide to hook that channel up to 2 speakers. both speakers are 4 ohm speakers. you have two choices in how you wire them. you can "daisy chain" them running the + from the + of the amp to the + of the speaker then from the - of the speaker to the + of the second speaker then the negative of that speaker to the - of the amp. This will maintain the 4 ohm load. However if you run a wire from the + of the channel to the + of each speaker and the - of the speakers to the - on the amp you will load the amp at 2 ohms. So when shopping for speakers pay attention to their ratings.

For what its worth.. my system sounds good inside and out.. I have a 12 in the berth and it will not shake any panties off, but sounds good cruising and while in boat or out. Someone always has a system that will blow mine away. ( have friend with huge peavy he throws on the hatch.. can't compete) so I do have a Bose portable sound dock that I can play on the beach for 4 hrs per battery that sounds awesome.. (Bose!!) So that's what I do!! No need to worry about draining engine batteries or house battery.

Ok if it were me I would get 4 10" subs under the seats. two under the bench (remove the 6x9") one under captains chair and then one under the other front seat. Then get four 6.5" (or 7 o 8" if you want) coaxials or component up high on the sides.

For the amplifiers you get the RMS rating of the drivers and then get an amp that is 125% of that rating for the mid/hi speakers and 150% or more for the subs.

Ok makes sense...thanks. Any suggestions on actual equipment?

Sounds good but a little excessive for what i need haha

Speakers, avoid the duel, lanzar, boss, pyle cheap junk. If money is not an object, jl is good chit. Amp's...Im not up to date on, I prefer old school underated stuff. I have an old Hifonics zues that has been thru hell and back and still works great. The old fosgate punchs (punch 45 etc) put out some power but the fosgate stuff didn't take a beating without crapping out. As odd as it may seem, one of the best sub amps I ever had was a Craig 500 watter. it survived 10 years of desert pounding in my old prerunner, a fire and subsequent douching by the fire dept and that thing still pushed a pair of 12's with ease.

Some are going to disagree with me, but on a boat in open air, less then ideal speaker placement for staging etc real fidelity goes out the window. A midlevel speaker like mtx is fine, unfortunately they don't make the 7.7's anymore. I don't care what your wife says, size matters, cone area moves air. the bigger the better for the most part, but after 6.5 's your choices get limited. Sub's, I don't really think you need 6 10's. If you build the correct sized boxes 2 or 4 will do it. I have heard a single 12 in the CORRECT box with correct power out do a bank of 10's.

You best improvement is going to come from matching your stuff, having enough headroom, then taking the time to tune it, the gains, cross overs, box size and sealing.

Good info. As far as the box goes...will I have to build one and put it under the seat or could I just use the enclosed area under the seat as the "box"

Impedance = resistance

The lower the number, the higher the resistance. If you have ever been to a concert, those amps and speakers are 16 ohm or higher.....your home is 8 minimum (just look on your receiver)

The higher the impedance....the more "headroom" (clear sonic reproduction) you achieve.

Some high impedance systems exist in car. Tsunami by gm, delco/Bose in early/mid 80's vette.....1/2 ohm. Sounded like azz, but LOUD!

Now to wiring.....two 4ohm speakers wired in PARALLEL ( +'s together as well as -'s and back to amp to same terminals) is a 2 ohm load.

Two 4 ohm speakers wired in SERIES ( + of amp to + of spkr 1, - of spkr 1 to + of spkr 2, - of spkr 2 to - of amp) creates a 2 ohm load on one channel. So, if it is a mono (bridged/bring able) amp, you are using the combined power of both channels.

This brings us to the next conundrum.....

Is your intended use sonic quality, or max out put? Headroom (sonic quality) goes down as the impedance drops.

Bass is mushy....muddy....meaning sound quality is really a non factor. I recommend finding a good class d amp that is mono and 2 ohm capable. I am not demeaning bass in the equation, as it represents 1/3 of the audio spectrum AND lifts the remaining 2/3 of the audible spectrum.

DEI and MMATS are two very affordable brands that can perform well for any budget....as well as MTX. Outside of these three, you are compromising quality, or hitting your wallet.....

For mids and highs, it is an entirely different process of thought. 2ohm and below is simply foolish. Stick with a 4ohm STEREO amp (non-class d) and use quality component speakers. Co-axial speaker are rubbish if there is no external passive crossover. Also, stay away from out of round speakers. 4x6, 5x7, 6x8, 6x9, 4x10

Do yourself a favor:

Put your amps in the cabin. Does not matter if they are ipx rated.....they are in the cabin....however....

Buy speakers that have a rating of ipx 13 of higher for marine use. Forget water....the sun will kill a speaker cone fast without a designation for marine use.

Ok....there are many more variables.....but u have the basics....

Buy what you think is going to suit your needs....not brand specific....but use the info above to guide you.

I personally have a clarion head, wired remotes, MMATS amps on jl 12's, and jl amps on jl 7.5's

Commander, what do you say on subs? Im running a DEI 1200/5 so my sub channel is class D 1 ohm stable So I have 300~600 watts, Just looking for 2 10's. I can glass in boxes if needed, but would rather not spend 2 days hanging upside down and severly contorted to do it.

Nahh

209 watts 15 year old Autotek amplifiers G&S Crossover four sets of 6.5" component speakers in the cockpit 1 set of 6.5" components in the swim deck 3 12 subs