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shaneirl
06-28-2011, 11:07 AM
i was told my enclosure needs to be 3.5 cubic feet so i calculated it up and found the box needs to be 33"x12"x15" .. thing is i want the back of the box to be angled to sit flush to the cars back seats and i want the front to be sligtly angled back just for looks ... how do i account for this?
also how do i figure out what size to make the slot port?

fasfocus00
06-28-2011, 11:11 AM
algebra rules!!!

[WxHx(D1+D2/2)]/1728=

shaneirl
06-28-2011, 11:17 AM
eeehm ye haha ..
what do i write in instead of the letters if you dont mind me asking?

fasfocus00
06-28-2011, 11:21 AM
width
length
depth1
depth2

shaneirl
06-28-2011, 11:26 AM
are the depth measurements just the width of the angled pieces?
... i was told the port tuning should be between 36 and 40hz how do i calculate that?

pro-rabbit
06-28-2011, 11:27 AM
eeehm ye haha ..
what do i write in instead of the letters if you dont mind me asking?

You will need to figure out what space you need, then figure out the port area required, then the length to get the tuning you want. Then you need to figure out the displacement of the port and sub(s). Add the displacement to the required air space to find out the total air space required for your enclosures.

Then you can figure out the actual size of the enclosure.

Might be a bit easier for you to learn if you purchase a design from some one and then work backwards from the finished product.

fasfocus00
06-28-2011, 11:33 AM
are the depth measurements just the width of the angled pieces?
... i was told the port tuning should be between 36 and 40hz how do i calculate that?

you measure top depth of box and bottom depth, you are not figuring out angles. you'll have to use Pythagorean theorem to figure out angle or a good protractor on a sketch. tuning is personal preference. I personally prefer around 36hz and most of the forum will recommend 30-32hz.

shaneirl
06-28-2011, 11:43 AM
oh yes i get you now .. top depth is 4" bottom is 12" .. i will find a calculator later on and calculate that.
thanks for the equation.
i will be listening to rap mostly so it will be long deep bass i want but i want to be still able to hear the short bass too.

shaneirl
06-28-2011, 11:44 AM
You will need to figure out what space you need, then figure out the port area required, then the length to get the tuning you want. Then you need to figure out the displacement of the port and sub(s). Add the displacement to the required air space to find out the total air space required for your enclosures.

Then you can figure out the actual size of the enclosure.

Might be a bit easier for you to learn if you purchase a design from some one and then work backwards from the finished product.

so i kind of account for the port in the volume of the box? ...
how much are a set of plans roughly?

pro-rabbit
06-28-2011, 11:47 AM
so i kind of account for the port in the volume of the box? ...
how much are a set of plans roughly?

You can click the link my sig which will take you my vendor section and list of prices for designs...

If you are doing a slot port you will the H x W x D/1728 to find the total displacement of the port.

shaneirl
06-28-2011, 11:53 AM
il look in the link now ... after i find the total displacement of the port how do i know what hz it is?

pro-rabbit
06-28-2011, 11:54 AM
You have figure out port area and length prior to figuring out displacement. You can not figure out displacement of something that has not been determined yet.

brandinooooo
06-28-2011, 12:00 PM
il look in the link now ... after i find the total displacement of the port how do i know what hz it is?

WinISD can help you with that. Its very simple to use and its free. Just put in the T/S parameters of your subwoofer and then put in the box size and desired tuning and it will tell you the length needed for the port.

pro-rabbit
06-28-2011, 12:02 PM
WinISD can help figure out port length and air space if used correctly.

shaneirl
06-28-2011, 12:04 PM
sorry about all these questions as im new to all of this but say i want 36hz ... where do i go from there
EDIT: sorry didnt see above posts

pro-rabbit
06-28-2011, 12:06 PM
you need to figure out port area first...then you can figure out the length

shaneirl
06-28-2011, 12:06 PM
WinISD can help you with that. Its very simple to use and its free. Just put in the T/S parameters of your subwoofer and then put in the box size and desired tuning and it will tell you the length needed for the port.
thanks for that .. il download it now and give it a go