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sweenster123
03-14-2009, 11:42 AM
How do u know what to deduct for bracing? :confused:


Ok and for port displacement. im not entirely dumb i promise just havent reallt built a box to a specific spec like this one.

pr-festiva
03-14-2009, 11:47 AM
it depends on the shape,,LXWXH for some thing like a 2x4 RXRX3.14Xlength for dowels both in inches then devide that by 1728 to get how many cubes it takes up.

blackdragonaudi
03-14-2009, 11:47 AM
What he said

sweenster123
03-14-2009, 11:48 AM
it depends on the shape,,LXWXH for some thing like a 2x4 RXRX3.14Xlength for dowels both in inches then devide that by 1728 to get how many cubes it takes up.


thanks thats what i was thinkin but wasnt sure. :D

PioneerSPL1990
03-14-2009, 11:49 AM
if its a square board cut if half corner to corner its likely a 45 degree angle. so double it back up, giving you an imaginary square to work with and do the above, then divide by to and theres your displacment.

sweenster123
03-14-2009, 11:50 AM
Ok and for port displacement. im not entirely dumb i promise just havent reallt built a box to a specific spec like this one.

PioneerSPL1990
03-14-2009, 11:53 AM
look up cylindrical volume calculator. use the circumfrance calculator. thats you best bet. and to exactly measure the port i'de use a cloth ruler.

sweenster123
03-14-2009, 11:56 AM
what would you recommend for port size? How many square inches going to be ported around 35Hz



look up cylindrical volume calculator. use the circumfrance calculator. thats you best bet. and to exactly measure the port i'de use a cloth ruler.

pr-festiva
03-14-2009, 11:59 AM
that depends on sub used and box size,,what ya useing?

sweenster123
03-14-2009, 12:06 PM
that depends on sub used and box size,,what ya useing?


Im going with 2 15" re se's d2. Box size before port and bracing displacement is roughly 8.8 cubes. im hoping between bracing and port displacement it will come down.

pr-festiva
03-14-2009, 12:16 PM
need to know how much brace displacement your gonna have and how much the subs displace also

sweenster123
03-14-2009, 12:21 PM
that figure is after sub displacement. i dont know on bracing. i havent figured it yet but im going to brace the hell out of it. so i guess ill have to wait to actually get it build to port it. im going to do a removeable port. i have another question tho. i have a 4 door kia back seat is coming out so i can do this. what way would you recommend facing the port. and same goes for the subs. forwards or up?




need to know how much brace displacement your gonna have and how much the subs displace also

pr-festiva
03-14-2009, 12:27 PM
all cars react different to loading you will have to just experiment to find out which works best.pioneerspl1990 is doing a half wall in his car he might be able to give a couple pointers.the half wall i tryed in my mustang ****** lol

sweenster123
03-14-2009, 12:29 PM
you could consider this a half wall its gonna be about 12 inches from the ceiling of the car. its gonna be interesting. im hoping for a good outcome. guess ill see.




all cars react different to loading you will have to just experiment to find out which works best.pioneerspl1990 is doing a half wall in his car he might be able to give a couple pointers.the half wall i tryed in my mustang ****** lol

IDSkoT
03-14-2009, 12:34 PM
How do u know what to deduct for bracing? :confused:

You find the area it takes up. ZOMG. If it's a dowel, use the cylinder formula, if it's a brace made out of 2x4, or whatever, just use the area (LxWxH). It's not that complex of a concept...


Ok and for port displacement. im not entirely dumb i promise just havent reallt built a box to a specific spec like this one.

Port displacement is the amount of space the port displaces and will solely rely on the tuning of the box and the width of the port...

Answered.

pr-festiva
03-14-2009, 12:44 PM
you could consider this a half wall its gonna be about 12 inches from the ceiling of the car. its gonna be interesting. im hoping for a good outcome. guess ill see.

just do a full wall at that point:)

IDSkoT
03-14-2009, 12:48 PM
you could consider this a half wall its gonna be about 12 inches from the ceiling of the car. its gonna be interesting. im hoping for a good outcome. guess ill see.

No such thing as a half wall....
The point of a wall is to cut the car's cab in two, while using the back as a huge sub box (even though there will be wood up there). It ensures a higher number because there will be less flex and less area to pressurize. (In terms of SPL.)
"A half wall" is just a big box and the only thing it has to do with a wall is that it's a sub enclosure.

Most people leave their sub box under the window line, for security reasons, and so they can see out their back window. If you can't see out of your back window... do a full wall, or cut down the height.

pr-festiva
03-14-2009, 01:07 PM
just used the term half wall in a generic way.easyer then saying box where back seat used to be

IDSkoT
03-14-2009, 02:32 PM
just used the term half wall in a generic way.easyer then saying box where back seat used to be

... that just makes it a big box.

pr-festiva
03-14-2009, 02:47 PM
pioneerspl1990's is looking an awful lot like a half of a wall,,and this dont seem like something to dwell on

sweenster123
03-14-2009, 04:42 PM
ok so its just a big ****n box. but yea thanks for ur help guys.