2 12"s or 1 15"???

[nauty220]

Would appreciate any comments on the pro's/con's of going from 2 12's to 1 15". I definitely have the power to push either but it was suggested to me to go to 1 15" for my 230.

[EarmarkMarine]

If the only consideration is surface area, the dual 12s will have a third more effective cone area than a single 15 and should generate an additional 1 dB + output.
Certainly a single location will be superior to separate locations if all else is equal.
However, past a point it will be the enclosure that dictates the low frequency extension and not the woofer. So, it's more logical to begin with which enclosure ideally fits the boat and allow that enclosure displacement to determine both the loading type (air suspension, bandpass, bass-reflex, etc.) and the specific woofer size and T/S parameters. If you are going for max output and max deep bass extension with something that is musically plausible then picking the woofer size first is placing the cart before the horse.
Boat = enclosure location and displacement = enclosure type = woofer selection = amplifier selection in that order only.

David
Earmark Marine