Thread:

Ported or passive radiators in a marine environment?

I know ported boxes give better bottom end response, but I don't want the chance of getting water inside my ported box. Is a passive radiator setup another direction to look?

I want to take the rear seat pedastal and make it a speaker box, instead of the aluminum legs that are there now. The area I have is roughly 8.3 cu-ft, and if I used all the room available, could put 4 12's down there. 4 12's would likely sound better than 2 12's and 2 12" passive radiators, but again - water in the ports would be my concern.

Suggestions?

Ported downfire!

OOPS, there is supposed to be a divider in between the two sides.

2 RESX12's in 2.0 cuft ported enclosures getting about 1600w would do the trick. How do I know? Thats what the last boat had and it would make ripples in the water. I would stand the box off the floor and downfire the ports. they will need to be about 12"x2.5" and 24" long for 32-34hz tuning from what I remember. I had 12 mids and the bass definitely could overpower them, just perfect! I would also mount your mids on your hard top to get the sound out like a wakeboard boat.

I think you still have Daves # right

EDIT, crap, I thought you had a hard top on that thing, nevermind, there's nothing you can do, just give up.

Originally Posted by H2oSki2Fast

I disagree with you, but to each their own. Shouldn't make a difference what musib you listen to with a properly designed enclosure.

ok...let me rephrase that. To get the most out of your system, music preference should be taken into consideration when tuning a vented enclosure.

Originally Posted by thmper321

Most 12" woofers need about 2.5 cubic feet in a vented enclosure.

Also when choosing a woofer a lower Qts means the sub will work better in a ported enclosure. Make sure the Qts does not go above 0.5

Qts should be listed in the owners manual.

Loaded down and ported down would be good. Better than both forward.

You're starting down that road of greek to me, but specs I have. The subs I will likely use have a Qts of .30, and the website says to give them 2.0c/f @ 33hz.

http://www.reaudio.com/specs.html#sp_sx

Again, the only problem I think I'd have with the box loaded and ported down firing is size. I want this to be the base of my back seat, and if I make it too tall, the seat base will be too high off the floor. I want the people in the back to be somewhat encased in the boat, not sitting on top of it. This gives me roughly 13" from the floor to the top of the box.

The speaker mounting depth is 6.5", so with 3/4" MDF on the top, that's already 7-1/4" out of 13. I guess that would leave 5" for the forward facing port - maybe that would work - but it shrinks my available cu/ft area.

Originally Posted by STV_Keith

You're starting down that road of greek to me, but specs I have. The subs I will likely use have a Qts of .30, and the website says to give them 2.0c/f @ 33hz.

http://www.reaudio.com/specs.html#sp_sx

Again, the only problem I think I'd have with the box loaded and ported down firing is size. I want this to be the base of my back seat, and if I make it too tall, the seat base will be too high off the floor. I want the people in the back to be somewhat encased in the boat, not sitting on top of it. This gives me roughly 13" from the floor to the top of the box.

The speaker mounting depth is 6.5", so with 3/4" MDF on the top, that's already 7-1/4" out of 13. I guess that would leave 5" for the forward facing port - maybe that would work - but it shrinks my available cu/ft area.

Keith, you can make the whole box to keep it off the floor. Just make it wider (the width between the sides of the boat) and have a slot ported enclosure built that side fires or down fires. The key is keeping the port inside the box. Either down fire the subs or front fire them.

My subs and ports point forward but you might not want to have any openings facing forward in your type of boat.

Originally Posted by SPL2K

Whats the max outside dimensions you have to work with?

This guy will get you where you need to be but the total amount of space you have is the determining factor.

The RESX12's need 2.0 cuft ea plus the port.