amp for sub

i have blown my old fosgate amp and looking for a new one. the sub is one 12" infinity 120.3dvc

here are the sub specs: http://www.crutchfield.com/p_1081203...ures_and_specs

says 300 rms and 1200 max rms, its dual voice coil and impedance is 4 ohm. since its a dual voice coil does that mean its wired for 2 ohm? or should i still be looking for a 4 ohm amp for this sub???

also ive been looking at a rockford fosgate 250a2 amp when bridged will give 250 watts rms at 4 ohms, will this amp be a good match up?

Its a 4 ohm DVC so when wired in parallel you're looking at 2ohms. Don't look for anything under the rated RMS so a minumum of 300 wats at 2 ohms but better would be 400-600 so you can have a little head room. There are loads of options in this range just look for a class D mono block .

Favored brands on Wake World are:
Exile
Wetsounds
Arc
JL Audio
Kicker
Zapco
Alpine
Boston Acoustic

They all make excellent options for you.

^^^^Dead on. You really need a monblock because you can't safely bridge a two-channel amplifier into a 2-ohm load.
Or, you can bridge a 4-channel amplifier into two channels and run each 4-ohm voice coil independently if you have a spare 4-channel amplifier laying around.

David
Earmark Marine

thanks for the help guys, not looking to upgrade to multiple subs this summer just looking to get my one 12 back in the boat and working. next summer i want to add a sub, but in my 2004 supra the only place i can add a sub is in a separate box since my rear lockers have 750LB sacs in each. so since i cant fit a box with 2 12" subs i have to have a sub under the drivers dash and a sub under the passenger side compartment.

is it possible to get an amp that is two channels pushing the 400-600 watts yall recommended at 2 ohms to each side, and only use one channel of that this summer for my 12, then next summer when i add another 12" sub i can just attach it to the other channel????

and finally with an amp pushing 400-600 watts per channel and my sub only rated for 300rms how to i not blow the sub? do i just put the gain at like 50% if the amp is rated at 600? (600watts x 50% gives me the 300rms my sub can handle?)

Eric,
I missed the part where someone may have recommended a second sub. In fact, I am generally against multiple subs with different orientations in different locations. Unless you are doing something totally over the top I would never use the port side locker in front of the observer's seat. With the seat closed you are wasting a ton of energy plus the conflicting phase issues are serious. You can overcome some of these obstacles with enough power and enough speakers but you don't have to. I am of the opinion that you should stay with a single subwoofer under the driver's helm console and simply go with a better sub, enclosure and power. It will be more productive. Think quality over quantity.

David
Earmark Marine

ok thanks for the advice, like i said im just looking for a cheap amp to get me through the rest of summer with a working sub, next year maybe ill just upgrade my whole system to a better sub and amp that will make a big difference.

just so i can start looking around trying to figure out what i want for next year or a winter project what are some good single subs that will produce alot of bass?

Eric,
There are all types of subwoofers. There are paper subs that are higher resonance, light, quick and responsive. Lots of SPL. There are heavy subs that will go deeper, rumble and thump like crazy but are slow and inarticulate with very little in the way of transients. There are woofers that will handle megawatts but are like moving a telephone directory in and out several hundred times a second. The amount of power required becomes enormous to get the speaker to perform. Extreme designs are often accompanied by extreme trade-offs in another but still important area. The best woofer is often a matter of balance. Its got to match up with the power amplifier and that has to match up to your budget.
We like to use JL Audio subwoofers in many cases and here is why. Engineering. Its in-house. They don't slap a label on someone else's product. JL Audio is one of the few that use Finite Element based modeling including Dynamic Motor Analysis. They are fanatical about making great sounding woofers and we have found them to be generally more musical and accurate.
JL Audio has seven automotive series and three dedicated marine models. They make everything from an 8-inch woofer to a 15-inch woofer. And with seven different series you can precisely match the thermal power handling and responsiveness to your application and power. They also provide very detailed and accurate Thiele Small Parameters on all their woofers so we can computer model the right enclosure for any boat. Don't forget about the enclosure as part of the subwoofer circuit as its just as instrumental in the bass performance as the actual driver.
More bass is easily accomplished by a larger woofer with more surface area. So the bigger the better until it conflicts with the available space for the enclosure. Forcing an oversized woofer in an undersized enclosure is the wrong route to go.
So start with the boat and where you intend to locate the sub. Then determine the available space for the enclosure. That displacement will usually dictate which size of subwoofer and which type of enclosure loading will be optimum.
We like to look at each boat independently.

David
Earmark Marine