Subwoofer install in my boat

firemancdw

I have installed four mm651 component speakers in my boat and I am seeing if I can install 2 mm840 8 inch subs under the back seat. I was wondering if these sub need to be sealed in an enclosure or can the be installed free air? Any info would be appreciated, Thanks Clayton

Jstas

Going by what Kim said, is your back seat sectioned off from the rest of the hull or is it open to the bilge anywhere? If it's open, you'll likely need to either seal it off or build an enclosure. Be careful though, the vented section may not be big enough to provide enough air flow to act as an infinite baffle. If it doesn't provide enough air flow, the varying pressure to vacuum to pressure oscillation will be destructive to your subs and sound absolutely awful. Especially if the air space is too large (bigger than 1.2 cubic feet) for the subs to pressurize properly.

I would not recommend sealing off the open section if it vents to the bilge because it may be designed in and necessary to prevent fumes from building up in the bilge. That or air pressure. Either one is bad. Might also help with moisture dissipation.

If you do have to build a box, I would build the box from marine grade plywood and then cover it in either marine epoxy or fiberglass resin to protect it. Go sealed. Vented on a boat...yeah, like a screen door on a submarine. Also, if you can mount it free air in the back seat, I would get a piece of marine grade plywood as backing for the subs. They will rattle and crack fiberglass and may weaken a bulkhead joint of a wooden boat without some baffling to strengthen the mounting points.

Also, use marine grade wiring and connectors. If you use standard stuff, it corrodes very quickly, especially in a saltwater environment. You should be able to get the wiring stuff you need as well as the plywood and resins at any marine supply store

Vance01

A speaker system is a must for entertainment and when it comes to the size of the speaker then I suggest you opt for quality and not size of the system. There are speakers available in varied sizes and structures and if you wish to have the best surfing experience then opt for high quality speakers.