will this work?

[Moe Lester 10+ year member]

the box is 21.5 tall and 21.5 deep and 41.5 wide? thats like 9.26 cubes before port lol.

 

[Raven 10+ year member]

It'd get loud, and it'd get low! Oh yeah. =p However, I don't even think my entire trunk could hold 9 cubes. I hope your camero has a LOT of trunk space.

 

[traksta15 10+ year member]

i guess i put the numbers in wrong.im about to just keep the prefab sealed one i have.....

 

[MrCabinetry 10+ year member]

What exactly are you shootin for with with enclosure?

Your last design was pooched on the port lenght given the port size and tuning frequency.

If the dims for the last design are external dims, you get this.

Gross Vol. = 9.26 cu.ft.

Net Vol. = 8.29 cu.ft.

Slot Port = 4" w x 20" h x 19" l @ 33Hz

 

[traksta15 10+ year member]

i want 3.5-3.6 cu. ft^3, with 33Hz tuning....the subs are going to be on the top side of the box, cause i want it to be hitting the back glass of my car. it can b 40" wide MAX, and the depth doesn't realy matter, just as long as it's aroung 20, 24", and height doesn't matter really, as long as i can still see out my back window.....is this possible?probably not, with this box i haven't had the best of luck........

 

[Moe Lester 10+ year member]

ive got a set of plans that is 37 wide, 13.5 tall, 19.5 deep tuned to 32 that id sell you, PM me if ur interested.

 

[MrCabinetry 10+ year member]

i want 3.5-3.6 cu. ft^3, with 33Hz tuning....the subs are going to be on the top side of the box, cause i want it to be hitting the back glass of my car. it can b 40" wide MAX, and the depth doesn't realy matter, just as long as it's aroung 20, 24", and height doesn't matter really, as long as i can still see out my back window.....is this possible?probably not, with this box i haven't had the best of luck........

So, you want 2 subs 3.6 cu.ft. per sub tuned 33hz common chamber.

What subs you going to be using and how many watts total?

 

[traksta15 10+ year member]

no, 2 subs (pioneer 2000spl's) in a 3.5-3.6 cu. ft^3 TOTAL...(about 1.75 apiece)

 

[MrCabinetry 10+ year member]

So, you want 2 subs 3.6 cu.ft. per sub tuned 33hz common chamber.
What subs you going to be using and how many watts total?

OK, SCRATCH THIS DESIGN OF THE LIST, BE BACK WITH REVISED SPEC'S

Here ya go:

40" w x 20" h x 21.5" d

Slot Port - 4" w x 18.5" h x 20.75" l @ 33

Gross Volume - 8.24 / Net Volume - 7.22

1 Slot Port Wall - 18.5" h x 16" L x 3/4"

The turn for the slot port isn't required since the center line length at the turn plus end correction will total the rest of the slot port lenght required @ 33Hz.

Now, if you want to throw some additional bracing into the enclosure, that will know down the net total volume @ 7.2 cu.ft.

If you really want to bracing the he!! out of it, increase your depth another 1/2" and your still within you volume and tuning spec's, just increase the lenght of the port wall the same amount by 1/2".

Phil

Woodlawn Cabinetry

 

[MrCabinetry 10+ year member]

OK, SCRATCH THIS DESIGN OF THE LIST, BE BACK WITH REVISED SPEC'S
Here ya go:

40" w x 20" h x 21.5" d

Slot Port - 4" w x 18.5" h x 20.75" l @ 33

Gross Volume - 8.24 / Net Volume - 7.22

1 Slot Port Wall - 18.5" h x 16" L x 3/4"

The turn for the slot port isn't required since the center line length at the turn plus end correction will total the rest of the slot port lenght required @ 33Hz.

Now, if you want to throw some additional bracing into the enclosure, that will know down the net total volume @ 7.2 cu.ft.

If you really want to bracing the he!! out of it, increase your depth another 1/2" and your still within you volume and tuning spec's, just increase the lenght of the port wall the same amount by 1/2".

Phil

Woodlawn Cabinetry

REVISION SPEC'S

40" w x 20" h x 16.25"

Slot Port - 4" w x 18.5" x 47"l @ 33hz

Gross - 6.08 cu.ft. / Net - 3.69 cu.ft.

2 Slot Port Walls

Port Wall #1 - 18.5" x 11.5" x 3/4"

Port Wall #2 - 18.5" x 29.75" x 3/4"

Throw in some bracing and you good to go.

Here's a parts list if this floats the boat:

Front & Back - 40 x 20 x 3/4

Top & Bottom - 40 x 14.75 x 3/4

Sides - 18.5 x 14.75 x 3/4"

2 Slot Port Walls

Port Wall #1 - 18.5" x 11.5" x 3/4"

Port Wall #2 - 18.5" x 29.75" x 3/4"

 

[traksta15 10+ year member]

thanks mr. cabintary, i appreciate the help, ive never seen somebody just give away box plans in that depth....but it's 3.5-3.6 TOTAL, about 1.75ish apiece, i'm running a HIFONICS BX1500D, so i'm guessing about 600-700watts.....thanks again for the help, i just need them smaller....

 

[MrCabinetry 10+ year member]

thanks mr. cabintary, i appreciate the help, ive never seen somebody just give away box plans in that depth....but it's 3.5-3.6 TOTAL, about 1.75ish apiece, i'm running a HIFONICS BX1500D, so i'm guessing about 600-700watts.....thanks again for the help, i just need them smaller....

Left ya a parts list if ya want to use it.

You could get the box smaller given that your only driving 700 watts between the subs...... that port size could come down a sh!tload, that'll save ya so room as to the size of the enclosure being smaller

Phil

Woodlawn Cabinetry

 

[traksta15 10+ year member]

http://gallery.caraudio.com/vg/1/0/6/0/5/project123_992689.gif

here's the one with the "21.5" height, it was supposed to be around 11".....what are the specs on this one?

 

[MrCabinetry 10+ year member]

http://gallery.caraudio.com/vg/1/0/6/0/5/project123_992689.gif
here's the one with the "21.5" height, it was supposed to be around 11".....what are the specs on this one?

By my calculations for that enclosure, the net vol is 2.144 cu.ft and that port size tunes the port to 49.31 hz.

 

[traksta15 10+ year member]

http://gallery.caraudio.com/vg/1/0/6/0/5/last_box_534534.gif

OK...i think i FINALLY figured out the big formula on jl's site, and did it all about 3 times (it was kinda fun), and i HOPE i got it all right.....a lot of it was guess work,i first used an online calculator that gave me a port length of 20, so i did it and got like 40 something tuning, so i bumped it up to a 32L and came out at just under 33 (like 32.7).and thanks again for all the help guys......

 

[traksta15 10+ year member]

bump....

 

[Moe Lester 10+ year member]

your port in that drawing is 38" long due to the end correction, and the bend in the port

its only 3.92 cubes internally also, you accidentally calculated the external dimensions as internal volume.

i believe your main problem is that you dont know what the port is going to displace before hand. You know that you want 3.5 cubic feet, you know that you want ~70 square inches of port, you know that you want 33 hz. calculate how long your port is going to be FIRST. then you can calculate the port displacement properly. when you have port displacement, add that to the 3.5 cubes you want, and add .166 for the sub displacement. you should end up with something like 5 cubes internally. this might get you started.

also, draw your box as if the wood has thickness. try filling in dimensions on these plans here and see what you come up with. calculate the airspace in 2 chambers, to the left, and to the right of the dotted line.

 

[traksta15 10+ year member]

how did u figure in end calculation?isn't it like half of something added on or sumthin like that?what #'s did u use?i thought i used the internal dimensions to calculate the box volume...i put the measurments were all external, but i thought i used the internal dimensions for the volume, also, i want AT LEAST 3.5 cuft^3 but 3.9-4 TOPS.....thanks for the help.......

 

[8inw7 10+ year member]

For end correction on a slot port deal, you're supposed to think that the end of the port theoretically goes half the width of your port further. That is, if you need a 16 inch length and your port width is 6", you only need to really make your port 13" long because having one wall extend beyond gets you another 3 inches. Here's a picture of how it is and more explanation cause i know this probably made no sense...http://www.jlaudio.com/tutorials/ports/index.html scroll down for that one.

 

[8inw7 10+ year member]

your port in that drawing is 38" long due to the end correction, and the bend in the port
its only 3.92 cubes internally also, you accidentally calculated the external dimensions as internal volume.

i believe your main problem is that you dont know what the port is going to displace before hand. You know that you want 3.5 cubic feet, you know that you want ~70 square inches of port, you know that you want 33 hz. calculate how long your port is going to be FIRST. then you can calculate the port displacement properly. when you have port displacement, add that to the 3.5 cubes you want, and add .166 for the sub displacement. you should end up with something like 5 cubes internally. this might get you started.

also, draw your box as if the wood has thickness. try filling in dimensions on these plans here and see what you come up with. calculate the airspace in 2 chambers, to the left, and to the right of the dotted line.

You can make your dimensions exact so that you have exacct tuning of 33 hz and exact 70 inches of port and exact volume. In order to tdo this, you must set up a system of two equations...if you give me the max dimensions you could have for height and width, i can calculate it for you and explain my steps...