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BoxdGM
07-01-2008, 08:44 AM
i recently bought a box from someone who had it built for a 15" L7. i was wondering if you gurus wouldnt mind helping me out with what the port is tuned to and the internal size of the box.

Box: 18" tall by 32" wide by 24" deep made of 3/4" Mdf

Port: 3.5" wide x 16.25" tall x 13.75" deep

Thanks for the help, if im missing any important info let me know

GearGuy2001
07-01-2008, 10:05 AM
Alright Im sure someone will double check me but

After you subtract .75 around the demensions I come up with 16.5 X 30.5 X 22.5=11323 The Port takes up space as well so subtract 16.25x13.75x0.75=167

11323-167=11156/1728=6.45 Cubes

Also for the Port does it make an L turn of is it really only 13.75" deep?

edit: Im new at WinISD but I think the box is tuned to 34hz

BoxdGM
07-01-2008, 10:32 AM
ok cool thanks alot. the port made with a wall that is 13.75" on the shorter side, the longer side (the box wall) goes all the way to the back of the box, but theres no "L" shape to it just one shorter wall

GearGuy2001
07-01-2008, 10:36 AM
Yeah thats what I typed into WinISD, I think like I said Im just learning WinISD and it said 34hz

BoxdGM
07-01-2008, 11:05 AM
seems kinda high for a 15, but it made it alot louder

schrummy
07-01-2008, 01:19 PM
not to second guess gearguy but i always understood that the port is not part of the box and u have to add the port on to the air space. like if u wanted a 6 cubic foot box u would design that then find how long of a port and add it to the box plan.

i did the math and got 6.025 cubic ft net. will be less once u add the sub. i got 36 hz.

adam212
07-01-2008, 01:22 PM
yes the port will take up the volume so once you find the standing volume thats when you see waht the port is tuned to
also if those were the outter dimensions of your box it will be tuned higher too

GearGuy2001
07-01-2008, 05:37 PM
yes the port will take up the volume so once you find the standing volume thats when you see waht the port is tuned to
also if those were the outter dimensions of your box it will be tuned higher too

Yeah Im still learning this stuff so I knew I was close but the cubes I figured include the port area, so you subtract the port area? or in this case Port: 3.5" wide x 16.25" tall x 13.75" deep ?

Let me know

schrummy
07-01-2008, 07:02 PM
then the wood thickness so the 3.5 wide port would take up 4.25X16.5X13

adam212
07-02-2008, 11:10 AM
you add up the dimensions of the port or multiply and then divide by 1728 just as for cubic footage and you'll get a number probably a decimal and just subtract it from your box volume