new subs 12W3v3 x 2
 

I am new to this site, but have read/learned a lot from it so far. I am looking for some help on my new subwoofer set up.

I have a 2012 230 wake SeaDoo. Currently the sub is a 10" in a ported box, under the drivers console area. I want to change it up and put 2 12W3v3's in the storage area under the passenger's seat, where the cooler is supposed to go. We don't use that cooler anyways, so it would just fill up an empty space. The area under the seat is approx 32"L x 20"W x 12"H, so that's plenty for 2 12W3's. I was thinking of having a box made to have them downfire with a 3" gap and put a slot vent along the bottom. I know you guys on here really know about this stuff, so any help would be appreciated.

David_E_M, feel free to chime in. I've talked to you before, at earmark, and i know you know your stuff so i'm hoping you could help me.

I forgot to mention that the rest of the system is 4 JL 7.7 components off of a MHD 900/5 amp. The 5th/sub channel is what i'm going to use for the new subs. I figure if that's not enough, then i can always add a 1200/1 later.

Chris,
It is all going to begin with your 30 amps of charging capacity (not continuous duty and only at high rpms).
From there the system should be designed for maximum efficiency. Greater surface area certainly helps that cause.
500 watts, even strictly regulated and even when conservatively rated, is not nearly enough to properly drive twin 12W3s.
A single 12 in a bass-refex enclosure may have the same output as two 12s in sealed enclosures.
Downfiring can choke output if it restricts the radiating surface area in any way. For this reason, downfiring is often best used when it is 360 degrees.
A long slot has resistance and constitutes a port which is a filter of sorts.
So I see many concerns.
A great audio design has to start with the specific boat.
Once determing the sub enclosure size, one of the most important aspects is how you are going to get that radiation out of the seating console and into the open area. I can see you have already given that some consideration.

David
Earmark Marine