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tholley
09-09-2008, 08:26 PM
Hey I have never designed a ported box before and was wondering if there was someone that could design it and tell me the deminsions.

I will be using half inch mdf board and 4 bl 18's tuned @ around 27-30.

Thanks!

jbizzle
09-09-2008, 08:28 PM
:rolleyes:

Pioneer~Saturn
09-09-2008, 08:31 PM
Hey I have never designed a ported box before and was wondering if there was someone that could design it and tell me the deminsions.

I will be using half inch mdf board and 4 bl 18's tuned @ around 27-30.

Thanks!

.5" inch MDF=bad...use atleast one layer of .75"


But I might be able to give you a hand

tholley
09-09-2008, 08:31 PM
I know what you are thinking. This will be the largest system I have ever installed.... all this is going into an 08 tahoe.

edit: I have not ordered the board yet so whatever you recommend.

Thanks~

BushJ311
09-09-2008, 08:32 PM
you will want more than 1/2 "

3/4 in most areas. and double that up on the top at least

tholley
09-09-2008, 08:33 PM
How would one layer of 1" work?

RAM_Designs
09-09-2008, 08:34 PM
How would one layer of 1" work?

very well, but 1" mdf is a pain to work with in 4x8 sheets....that ish is heavy!

tholley
09-09-2008, 08:36 PM
Ok well I will go with 3/4 I have never worked with 1" before. But could someone set this up for me? Any help would be appreciated. I am hoping to have the parts ordered as soon as possible, hopefully next week.

99grandprixGT
09-09-2008, 08:39 PM
first they would need the max dimensions that your willing to use.

tholley
09-09-2008, 08:52 PM
4 feet from side to side 3 and a half foot from front to back and 2 feet give or take some top to bottom. There is some leeway in the top to bottom measurement I want to be able to make a slide to put on top of the box so I can still carry groceries and stuff without damaging the box or subs.

tholley
09-09-2008, 09:15 PM
Thats 24 ft cubed with a 2 foot heigth isn't it?

Pioneer~Saturn
09-09-2008, 09:16 PM
It should be a good 20 cubes for 4 18's...if not more

jbizzle
09-09-2008, 09:17 PM
You're not fitting 4 18's with 13 cubes with or without port and driver placement.

EDIT: Beat :(

Mr. Slate
09-09-2008, 09:18 PM
How much power?

Mr. Slate
09-09-2008, 09:19 PM
Double the 3/4 sheets all the way around.

MisterGrubbs
09-09-2008, 09:22 PM
No need to double all the way around. 3/4" all the way, double the top plate and build braces for it.

OP - You're going to need roughly 2x that space for four ported 18's, just to let you know. After box and sub displacement...yeah

So re-think it. Four 15's might fit you a bit more reasonably.

Mr. Opportunist
09-09-2008, 09:25 PM
I'd tripple it all the way around to eliminate the need for bracing. Less obstacles inside of the box, simplifies the process. Works out all around. I would go with birch rather than MDF as well just to save on weight...

Pioneer~Saturn
09-09-2008, 09:26 PM
I'd tripple it all the way around to eliminate the need for bracing. Less obstacles inside of the box, simplifies the process. Works out all around. I would go with birch rather than MDF as well just to save on weight...

x2 on birch. But price=:crap:

Mr. Opportunist
09-09-2008, 09:33 PM
x2 on birch. But price=:crap:
If he can afford 4 18s and the power required for them he should be able to afford birch... lol

Mr. Slate
09-09-2008, 09:34 PM
No need to double all the way around. 3/4" all the way, double the top plate and build braces for it.

OP - You're going to need roughly 2x that space for four ported 18's, just to let you know. After box and sub displacement...yeah

So re-think it. Four 15's might fit you a bit more reasonably.

Dude, I had a box with 2 Solo X 18s that was made out of 2" trupan all the way around.
My van had a wall with with 4 " all the way around.

Mr. Opportunist
09-09-2008, 09:35 PM
Dude, I had a box with 2 Solo X 18s that was made out of 2" trupan all the way around.
another good choice, couldn't think of the ******* name of it when I said birch... :crap:

MisterGrubbs
09-09-2008, 09:36 PM
Dude, I had a box with 2 Solo X 18s that was made out of 2" trupan all the way around.

That's great. +1 for you. I didnt say it wouldnt work, I simply said there was no need for all of that.

Yes, I'd rather have a box that was doubled up all the way around, but once again if you double the top plate and brace it correctly you dont need that.

All I said.

IgnoreMe
09-09-2008, 09:37 PM
It should be a good 20 cubes for 4 18's...if not more

20 cubes is not nearly enough for the bl's IMO.

i can tell you there was a very drastic and very positive response when i removed a 18" bl from a 5.5 cube box, into a 7.5 cube box.

IMHO, you need to shoot for at least 7 cubes per 18, IE 28 cubes net volume

Mr. Slate
09-09-2008, 09:39 PM
That's great. +1 for you. I didnt say it wouldnt work, I simply said there was no need for all of that.

Yes, I'd rather have a box that was doubled up all the way around, but once again if you double the top plate and brace it correctly you dont need that.

All I said.
You ever seen a box blow apart?

MisterGrubbs
09-09-2008, 09:39 PM
You ever seen a box blow apart?

Yup.

Mr. Opportunist
09-09-2008, 09:40 PM
20 cubes is not nearly enough for the bl's IMO.

i can tell you there was a very drastic and very positive response when i removed a 18" bl from a 5.5 cube box, into a 7.5 cube box.

IMHO, you need to shoot for at least 7 cubes per 18, IE 28 cubes net volume
I agree, I think the OP has watched too many of Meades vids and shouldn't choke the 18's off as he does. I think 4 15's would have better results due to space constraints.

Dtrickz
09-09-2008, 09:41 PM
Im running my 2 18's in 16 cubes. I'd atleast want 24-25 cubes for 4

Pioneer~Saturn
09-09-2008, 10:50 PM
20 cubes is not nearly enough for the bl's IMO.

i can tell you there was a very drastic and very positive response when i removed a 18" bl from a 5.5 cube box, into a 7.5 cube box.

IMHO, you need to shoot for at least 7 cubes per 18, IE 28 cubes net volume

Yea I would want to see around 7 cubes per 18, I was kind of setting a bare-minimum for what it should be

DBDRAGGUY
09-09-2008, 11:00 PM
OP may want to do a little research before embarking on such a large system.

3/4 MDF is a must, and needs to be braced and or doubled. 20 cubic feet would be the minimum I would go for 4-18's, anything less and you might as well just use 2 and get the same results.

tholley
09-12-2008, 04:32 PM
Ok so a 4 foot wide by 3.5 foot by 2 feet tall should give me enough space correct?

I will also be doing as grubbs suggested and use 3/4 all the way around and just properly brace it and double it up in some areas. Also I have still not decided on highs / mids, what would you guys reccommend?

Thanks!

tholley
09-14-2008, 04:12 PM
bump.

All help is appreciated. :)