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king ranch
03-11-2008, 08:18 PM
so i am trying to make my own box for 2 12's l7's ported

i used re audio box calculator

heres what i came up with
box width 35
box height 17
bottom depth 21
top depth 21
wood is .75
port width 4inches
port length 2 is zero

port lenght 1 is 16.25" but it says the total port length is 23" why does it say that

leaves around 5cuft net and at a 33hz tune will this work

also is the ox volume net and when adding up the net do you add the port displacement in with net or does it get used as taking up space

BrianChia
03-11-2008, 08:20 PM
yes.

king ranch
03-11-2008, 08:29 PM
yes to what it will work

also why does it say the total port length is 23" when it shows it being only 16.25

also with port displacement it should be right around 5cuft net correct

do you add the port displacment for net or do you subtract the port displacement from the voulme of the box

wats the formula for figuring out how much port displacement is

miker
03-11-2008, 08:31 PM
port area time length?

king ranch
03-11-2008, 08:33 PM
huh

miker
03-11-2008, 08:34 PM
width of port * height of port * length of port

Then do the same for the MDF you used to build the port, or just incorperate it into the port dimensions.

king ranch
03-11-2008, 08:39 PM
ok so 4x15.5x15.5 corret if thats true that gives me 961 but how do i figure out how much it displaces

dman4486
03-11-2008, 08:41 PM
ok so 4x15.5x15.5 corret if thats true that gives me 961 but how do i figure out how much it displaces

that is cubic inches...that is displacement

miker
03-11-2008, 08:42 PM
that would be 961in cubed.

Divide that number by 1728 (in cubed in a cubic foot).

king ranch
03-11-2008, 08:44 PM
so 961 divide that by 1728 gives me .55 thats how much it displaces or what

so is 5net enough for 2 12's l7's

miker
03-11-2008, 08:45 PM
Yup..

and, not a clue.

SPY
03-11-2008, 08:47 PM
The RE box calc takes the port displacement out of the box volume, all you need to subtract is the sub displacement.

king ranch
03-11-2008, 08:48 PM
how much displacement does a 12" l7 displace cant be more than .20 for 2 subs

miker
03-11-2008, 08:48 PM
The RE box calc takes the port displacement out of the box volume, all you need to subtract is the sub displacement.

didn't notice he was using RE.. lol

miker
03-11-2008, 08:49 PM
how much displacement does a 12" l7 displace cant be more than .20 for 2 subs

pretty sure AVERAGE displacement for a 12" woofer is .07

king ranch
03-11-2008, 08:59 PM
thats what i figured thanks

miker
03-11-2008, 09:03 PM
gl with the build.

king ranch
03-11-2008, 09:05 PM
well i will prob buy the wood and let them make all the cuts for everything so it should be pretty close to 100% anyway what are all the tools i will need and what kind of screws do i used and cocking

dman4486
03-11-2008, 09:08 PM
well i will prob buy the wood and let them make all the cuts for everything so it should be pretty close to 100% anyway what are all the tools i will need and what kind of screws do i used and cocking

wood screws, wood glue/liquid nails, screwdriver...

and i don't think anywhere that sells mdf can cut the sub cutouts, so you will need a router or jigsaw

miker
03-11-2008, 09:09 PM
All you NEED is a skill saw, clamps, and a screw driver.

You just make a guide out of straight 2x4's and you can get a prefect cut with out dealing with a table saw.

I use 2 1/4" finish screws in mine, and use a couple long as clamps as well.

Not really sure what a good screw is, but I have a lot of those lying around, lol.

king ranch
03-11-2008, 09:09 PM
well me and a friend and his dad are gonna try to build it and his dad is a welder so he should kno a lil about this stuff maybe and he has a router and my friend has built boxes before only sealed not ported

what would i use clamps for and also how far away do i space the screws out and whats the best way to atattch the port to the box

also how do i brace the box if its needed and also should i dobule baffle it

miker
03-11-2008, 09:10 PM
wood screws, wood glue/liquid nails, screwdriver...

and i don't think anywhere that sells mdf can cut the sub cutouts, so you will need a router or jigsaw

Or a rotozip! I use one with a circle guide thing.

miker
03-11-2008, 09:11 PM
well me and a friend and his dad are gonna try to build it and his dad is a welder so he should kno a lil about this stuff maybe and he has a router and my friend has built boxes before only sealed not ported

won't really be more dificult, just make sure you line the port up at 90 degree angles. (it's easy to acidently put them at an angle..)

dman4486
03-11-2008, 09:13 PM
Or a rotozip! I use one with a circle guide thing.

I think the last time I heard that word was Christmas a few years ago on whatever tv station has all the phoneathons!!

Awesome

king ranch
03-11-2008, 09:13 PM
well me and a friend and his dad are gonna try to build it and his dad is a welder so he should kno a lil about this stuff maybe and he has a router and my friend has built boxes before only sealed not ported

what would i use clamps for and also how far away do i space the screws out and whats the best way to atattch the port to the box

also how do i brace the box if its needed and also should i dobule baffle it

did you guys see what i added also how do i make sure its a 90 degree angle there will only be one piece of wood used for port there wont be a 2nd port length

miker
03-11-2008, 09:14 PM
I think the last time I heard that word was Christmas a few years ago on whatever tv station has all the phoneathons!!

Awesome

???? Whats wrong with them?

miker
03-11-2008, 09:15 PM
did you guys see what i added also how do i make sure its a 90 degree angle there will only be one piece of wood used for port there wont be a 2nd port length

well yeah.. a 90 with the front baffle. . .

dman4486
03-11-2008, 09:15 PM
nothing is wrong, i just havent heard anything of them till now...and it was qvc

miker
03-11-2008, 09:16 PM
nothing is wrong, i just havent heard anything of them till now...and it was qvc

Oh, ok. Sounded liek you were saying they were ****** or something.

I have just never used a router, so this is a super easy alternative.

BobbyDD
03-11-2008, 10:43 PM
well i will prob buy the wood and let them make all the cuts for everything so it should be pretty close to 100% anyway what are all the tools i will need and what kind of screws do i used and cocking

??:wow:

dman4486
03-11-2008, 10:44 PM
??:wow:

caulk

king ranch
03-12-2008, 12:56 AM
yes caulk lol sorry about that

also with those dimensions how many sheets of wood do i need

miker
03-12-2008, 01:17 AM
Sheets are 48" x 96"

maybe it's 108".. idk.. 8 or 9ft long.

king ranch
03-12-2008, 01:55 AM
so how can i figure out how much wood i need

also do i need to brace the box if so how would i go about that