Need box design please! (2) JBL W12gti MkII

mrjoeyjiffy · Feb 18, 2008

I was hoping someone could make me a sealed box design for 2 JBL W12Gti MkII subwoofers, they are going in the back of my 2001 tahoe (3rd row removed) and will probably be getting around 600-800 watt rms a piece(depending on which amp i end up going with) I want something reasonably loud, but tight hence the reason im going sealed and not ported. Here is a data page with all the T/S info, and as far as size limitations, i think about 40 inches wide and no more than 16-18 inches tall depth isnt really a concern but if i had to put a cap on it i guess i would say about 30 inches. Thanks in advance!

mrjoeyjiffy · Feb 19, 2008

Ok well I went out on my own and did some research //content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif and I believe I've came up with a pretty good box, comments suggestions are greatly appreciated!

Width 30.5"

Height 17"

Depth 29 3/4"

Vent height 15.5"

Vent Width 4 1/2"

Vent Length 21 1/2"

The idea was to make the location of the port provide "bracing" for the box so that no additional bracing would be necessary, is this a good idea?

Atimm693 · Feb 19, 2008

I got approx 7 cubes after port tuned at ~30 htz. Is this what you wanted it to be?

The port will add some bracing.

mrjoeyjiffy · Feb 20, 2008

yes i might make the box a dat bit shorter in depth, but its pretty close to what i want, should this box work well without any additional bracing?

Atimm693 · Feb 20, 2008

With that box bracing shouldnt be needed.

mrjoeyjiffy · Feb 20, 2008

will that be too much airspace? i want it tuned around 30 hz, the manufacturer says 2.25 cubic feet per sub in a ported box, but im thinking theyre saying the low end because most people are confined for space, would 7 cubic feet(closer to 6 cubic feet after port/driver displacement) be too much?

Atimm693 · Feb 20, 2008

will that be too much airspace? i want it tuned around 30 hz, the manufacturer says 2.25 cubic feet per sub in a ported box, but im thinking theyre saying the low end because most people are confined for space, would 7 cubic feet(closer to 6 cubic feet after port/driver displacement) be too much?

3 cubes net each, should work, and if you do make it too big you can add stuff to the inside of the box to make it smaller.

BuckyBoy · Feb 20, 2008

will that be too much airspace? i want it tuned around 30 hz, the manufacturer says 2.25 cubic feet per sub in a ported box, but im thinking theyre saying the low end because most people are confined for space, would 7 cubic feet(closer to 6 cubic feet after port/driver displacement) be too much?

If they recommend 2.25, then I wouldn't make it any bigger than 5-6ft^3 net.

mrjoeyjiffy · Feb 20, 2008

yeah they actually reccomend 2.25 including sub and port displacement, back to the drawing board...

mrjoeyjiffy · Feb 20, 2008

Alright I think I have this down, JBL calls for 2.25 cubic feet per sub gross, which would be 4.5 cubic feet for 2 subs, this box should have a gross volume of 4.7 cubic feet.

Box:

Width 28"

Height 14"

Depth 26"

Vent:

Height 12.5"

Width 3"

Length 18.4"

Should be tuned to right at about 30 hz, I think this should work well, any suggestions/comments/criticisms are welcome.

THUMPPER · Feb 21, 2008

stick with the recomended internal volume (2.25cf3) per sub plus

sub and port displacement and give it lots of port area

mrjoeyjiffy · Feb 22, 2008

will the 3/4 inch of space around the smallest parts around the edge of the subwoofer be enough to support it?

mrjoeyjiffy · Feb 24, 2008

for anyone who cares im nearly done with the box, just a few more things to do, here are some photos. Note to anyone who lets the guy at lowe's cut your mdf watch them, this lazy piece of **** would cut through it then come back through it with THE SAW STILL RUNNING, 2 belts on a belt sander and a half an hour later and i have them close enough to fit together but definitely not perfect. Anywho here are some pics

yuske · Feb 26, 2008

That looks good post the pics when all done i want to see.

By any chance how should i do a box for 3 w12gti subs at 2.25 tuned for 30hz i am trying to figure out where do i put the port since its 3 subs?

mrjoeyjiffy · Mar 8, 2008

ttt i have another question.

I've since decided on building a new box with that same design just a bit taller and a bit wider so i can achieve nearly perfect (at least to the manufacturer's specs) airspace, port, etc. And also because everytime i look at it i get pissed at ol dumbass will at my local lowe's for cutting it so terribly.

ANYWAYS, my question is without a double baffle and these subs being as heavy as they are(nearly 40 lbs from what i understand) should i build some sort of support for the back of the woofer? thanks in advance.

Search

Need box design please! (2) JBL W12gti MkII

mrjoeyjiffy
10+ year member

Senior VIP Member

mrjoeyjiffy
10+ year member

Senior VIP Member

Atimm693
10+ year member

Shadetree Mechanic

mrjoeyjiffy
10+ year member

Senior VIP Member

Atimm693
10+ year member

Shadetree Mechanic

mrjoeyjiffy
10+ year member

Senior VIP Member

Atimm693
10+ year member

Shadetree Mechanic

BuckyBoy
10+ year member

CarAudio.com Elite

mrjoeyjiffy
10+ year member

Senior VIP Member

mrjoeyjiffy
10+ year member

Senior VIP Member

THUMPPER
10+ year member

Pound That Sound

mrjoeyjiffy
10+ year member

Senior VIP Member

mrjoeyjiffy
10+ year member

Senior VIP Member

yuske
10+ year member

Member

mrjoeyjiffy
10+ year member

Senior VIP Member

Similar threads

About this thread

mrjoeyjiffy

GoldCountryCA

GoldCountryCA

Latest topics

Need box design please! (2) JBL W12gti MkII

mrjoeyjiffy 10+ year member

Senior VIP Member

mrjoeyjiffy 10+ year member

Senior VIP Member

Atimm693 10+ year member

Shadetree Mechanic

mrjoeyjiffy 10+ year member

Senior VIP Member

Atimm693 10+ year member

Shadetree Mechanic

mrjoeyjiffy 10+ year member

Senior VIP Member

Atimm693 10+ year member

Shadetree Mechanic

BuckyBoy 10+ year member

CarAudio.com Elite

mrjoeyjiffy 10+ year member

Senior VIP Member

mrjoeyjiffy 10+ year member

Senior VIP Member

THUMPPER 10+ year member

Pound That Sound

mrjoeyjiffy 10+ year member

Senior VIP Member

mrjoeyjiffy 10+ year member

Senior VIP Member

yuske 10+ year member

Member

mrjoeyjiffy 10+ year member

Senior VIP Member

Similar threads

About this thread

mrjoeyjiffy

GoldCountryCA

GoldCountryCA

Latest topics

mrjoeyjiffy
10+ year member

mrjoeyjiffy
10+ year member

Atimm693
10+ year member

mrjoeyjiffy
10+ year member

Atimm693
10+ year member

mrjoeyjiffy
10+ year member

Atimm693
10+ year member

BuckyBoy
10+ year member

mrjoeyjiffy
10+ year member

mrjoeyjiffy
10+ year member

THUMPPER
10+ year member

mrjoeyjiffy
10+ year member

mrjoeyjiffy
10+ year member

yuske
10+ year member

mrjoeyjiffy
10+ year member