E-rock

A year ago I had a box made for my subs and mounted it under the back seat. The guy who built it told me it wouldnt last and it didnt. The first time out it got wet it and swelled up. 6 months ago I saw my buddy trimming out the front door of his rental house with MDF and I laughed, telling him of my experience and said that that it would never last. He said it was a special waterproof MDF and that it was chepaer than regular wood trim. I disagreed. I decided to do a little test with it and took a couple scraps home and soaked it in water for 2 months and Ill be damned if he wasnt right. No swelling whatsoever. The only thing I noticed was that after about 6 weeks the surface that was exposed to air was starting to mold, however the one that was submerged didnt deform at all, not one bit. Im sold on the stuff and will definately be using it for the next box that I have to build, although I am still going to cover it in glass.

US1 Fountain

iTrader: (1)

Yrs ago I was into home construction and we built a 3 story building and also used an exterior grade of MFD for the store front that was just painted. Been over 13 yrs and it still looks good.

Wildman_grafix

Yea, never seen it make the response worst.

I didn't know you were in home construction, always thought you had always been a tool maker.

ALWAYS!

4bus

iTrader: (4)

I agree, doesn't really matter the shape, unless you are dealing with ports. In a sealed application it shouldn't matter.

However, you want at least 2-3 inches behind the deepest part of the speaker magnet for a sub woofer, to insure proper cooling for the voice coil.

You can test tune your box with and without the fiber fill. It will change the "note" of the bass with/without and with different amounts.

In high school my job was car stereos. You would be amazed the cob jobs you see, But my all time favorite was a guy that bought two great orion subs, and an orion amp from us, and returned because they lacked bass. The subs were in the truck, just laying on the carpet. The orion HCCA amp (prob at least $1000 at the time) was under the front seat wired into the fuse for the window wipers with 3 pieces 14 ga wire grouped on the positive side. The subs were fried from over excursion, and high distortion levels, he had been running it like this for weeks.

We replaced the speakers under warranty, even though we shouldn't have. And set him up with a box and proper wiring done in house. When completed he returned to let us know some of his car accessories were not working properly. He wired the amp to the non fused side of the fuse box, and metled the fuse box itself with the first amp install. He though we should pay for it, we declined, he sued and won half the money for the repair

Audiofn

Foam can add up to about 10% to your box size. You never want to over stuff it. It is like insulation. James loudspeakers is doing some really cool stuff with small speakers.

US1 Fountain

iTrader: (1)

Did some numbers crunching using some measurements.

Current setup;
I have approx 1.6 cu. ft of volume inside the storage compartment that is currently 'the box', which is fully sealed.
Infinite baffle JL sub, that specs min 2 cu. ft. if enclosed, 4 cu. ft preferred. So I'm undersized a good amount, which I figured.

I can make a box to fit thru the compartment opening to give me approx .8 cu. ft, using 3/4 board.
The enclosure type sub specs for box recommends .5-1.0 cu. ft. volume.

Sub housing will absorb .06 cu. ft.
Keep in mind this will be a box, within a box, if that makes a difference?

Would I be better off building a box, or utilizing the compartment and trying to fill with solid material to shrink the volume down? I suspect the FG wall thickness is 1/4" or so.
A new sub will be purchased for enclosure use.

Current setup isn't very boom boom, more of a muffled boom

4bus

iTrader: (4)

How big is the storage area? Is it the fountian we are talking about, or the baja?

If the storage area is sealed you do not want a box within a box. A double box, which can create a band bass and make more bass is great, however it needs to be ported, and sealed on the outside box is just going to cost you sound....lots of it.

Take a picture, or let me know what storage area you are talking about. If it is sealed and sealed well the sub will still work fine up to about 20 cu ft, but it must be sealed. The infinite baffle is designed for just such an application.

I have two 12" free air kicker subs in the fiberglass walls of the cockpit of my cruiser. Spent some time sealing and checking, adding dynamat every where, even built some bulk heads to keep the air from reaching places I did not want it. It was worth it, they pound hard, have full range sound for all music, and sound great with no distortion. FYI if you have midrange speakers using the same airspace, such as this application, make sure you install premade speaker baffles to protect the smaller ones from the air movement of the subs.

Look close, there are subs on the walls



A box I built in a 388 hustler, and yes the boat was already that dirty before I got in If you can go under the seat, it is the best location in a performance boat, IMO.

US1 Fountain

iTrader: (1)

[QUOTE=4bus;3590876]How big is the storage area? Is it the fountian we are talking about, or the baja?

If the storage area is sealed you do not want a box within a box. A double box, which can create a band bass and make more bass is great, however it needs to be ported, and sealed on the outside box is just going to cost you sound....lots of it.

/QUOTE]

In the Baja.
The storage compartment comes out to around 1.6 cu. ft.
Yes it is sealed. The inside is a 1 peice FG section glassed to the back side of the cockpit liner. The speaker next to it is just mounted in the side. Does not share teh same air space as the sub. I removed the door and made the panel to mount the sub in, using the existing screw holes. You can see the opening thru the cover as it has a darker tint. I do not want to alter the compartment in any way, so if I ever remove the sub, I can do so and just reinstall the door. The infinite sub recommends 2.0 at min, with at least 4.0 cu. ft for preferred.

A enclosed sub recommends .5-1.0 I can achieve that by building a box that will fit thru the door opening. But then that's the box with in a box.

Are you suggesting keeping my infinite sub? I'm way undersized on volume now. Not a problem to purchase the right sub. Thanks!
Thanks

4bus

iTrader: (4)

[QUOTE=US1 Fountain;3591009]Wow, nice to have a premolded sub box built on your boat hahah

What is the thickness of starboard you are using on the face of that sub enclosure?

What do you have for a sub amp?

Do you have the same enclosure on the other side? Subs work best in pairs, no question.

IMO, what I would do with that set up, and only one speaker, is build a ported enclosure. A ported box makes me the most noise with the least amount of power. It also fills the most space with sound. Sealed enclosures offer the tightest bass, and best sound quality, but require more power to get the same DB. Go with a 12" sub if you have the room. You don't need marine for today's subs IMO. A kicker solo baric 12" L7 DVC or JL audio 12W7 DVC would sound amazing in there with a square bass port exiting on the bottom. But you will need a 500x1 amp to push those.


To fix what you have I am not sure. Could be wattage, DB gain, or the box you have flexing. Is is strong glass or thin? If the box flexes the speaker will not be able to vibrate the air to make bass.

If you have the same cabinet on the other side you could also add an identicle sub and bridge the channel you are using, this will triple the bass effectively.

US1 Fountain

iTrader: (1)

[QUOTE=4bus;3591044]
Just the 1 compartment. That is the only location that was large enough and flat, thus the making use of the storage compartment. There is no other area large enough that is flat and open behind to add a 2nd sub. This is it.
Running off a JL 250 mono amp.
Compartment is solid, no flexing at all. Nice round corners inside add to the strenght of it. Face panel is 3/4". As you can see from the pic, There is room at top and bottom to port that 'box', but the JL site says not to run the infinite sub in a ported box.

It just sounds like the sub is beating against itself. Thanks