Box for 4 L7s

[vetkilr 10+ year member]

Is net after port/driver/bracing displacement? As of now I'm sticking with this 10.21 cubic foot box. 2 per ported would be worse if they were individually chambered, but since it's all one chamber, it should be better from what I've been told.

I would do 2 per incase one day you get another amp you can run one amp per 2 subs and then they will wang chung.

 

[PhatTonyDeMarco 5,000+ posts]

There is no difference audibly between individual chambers and a shared chamber. 2 cubes per driver is 2 cubes, regardless of shared chamber.

And yes, net is once everything has been deducted (Bass Box 6 does not calculate slot port displacement correctly either.)

 

[xpl0it 10+ year member]

Does it overcalculate or undercalculate?

 

[xpl0it 10+ year member]

Yeah you are right, if my port is 30"X3.5"X14.3", that's 0.96 cubic feet of displacement, BBP6 said it was 1.167 cubic feet.

14.3" being how deep the port is.

Edit: It's .91 cubic feet displacement, forgot i'm goin 1.5" baffle instead of .75"

 

[vetkilr 10+ year member]

Yeah you are right, if my port is 30"X3.5"X14.3", that's 0.96 cubic feet of displacement, BBP6 said it was 1.167 cubic feet.
14.3" being how deep the port is.

Edit: It's .91 cubic feet displacement, forgot i'm goin 1.5" baffle instead of .75"

Looks like it adds .75 on all sides to get that displacement.31.5*4.25*15.05=1.166

 

[xpl0it 10+ year member]

ah yeah actually 1 sec.

So wouldn't it be 31.5X4.25X12.05 of displacement? You'd subtract 1.5" from the deepness since the deepness of the port is calculated from the front of the baffle. So .934 cubic feet then.

 

[xpl0it 10+ year member]

So I'm lookin at 10.44 cubic feet now...

As far as running a smaller box and then adding more power later, I'm already going to run 3000-3200 watts on them. I'm having to do some major electrical upgrades already, getting another amp and strapping them would kill my upgraded electrical system. So the amp I get will be the one I stick with. I wish the Hifonics Colossus 2 was a little cheaper, but if I end up building this box, I'll pick up some extra cash vs. buying from John Nolte, so I guess I could get that colossus 2 over the powerbass xa-3000d now that I think about it.

 

[vetkilr 10+ year member]

What did you take out for Sub displacement

 

[vetkilr 10+ year member]

Your tuning to 36hz I take it.

 

[xpl0it 10+ year member]

37hz, sub displacement I used .46 cubic feet for all 4.

 

[xpl0it 10+ year member]

So actually, right now my box is 10 cubic feet even. Taht's after port displacement and driver displacement.

 

[xpl0it 10+ year member]

So would metal rod bracing or whatever take up minimal space inside the box.

 

[PowerNaudio 10+ year member]

the F3 is where your frequency responce starts rolling of to the -3dbs. 30hz is not a bad roll of point since cabin gains will bring that up way higher up to posible +6db but not sure maybe more maybe less.

the rods will take less space then the wood bracing and are allot stronger.

 

[xpl0it 10+ year member]

This looks off, why is it peaking around 60-75hz? I used the 2004 model driver specs (was just a fill in to create the box specs).

 

[xpl0it 10+ year member]

Anybody?