is a 4" port enough for a 12" bm???

[~Magick_Man~ 10+ year member]

i am building a box tomorrow and it turns out i have the room to make it a ported box so i want to go that route.

the box will house 2 12" si BM's

there is no good area to place 2 ports next to each other so i am planning on seperateing the 2 subs and each chamber will have a 4" pvc port

does this sound like it would work?

i will have some pictures of what i am trying to do in a little while

Thanks,

~Magick_Man~

Click to read more...

 

[~Magick_Man~ 10+ year member]

here is the basic idea i have right now.

it might change a bit but that is pretty much it.

so if i dont make 2 seperate chambers will the subs really utilize the area in the middle?

Thanks,

~Magick_Man~

 

[xluben 10+ year member]

you need double that port area.

have fun trying to make it fit //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

 

[bdawson72 5,000+ posts]

heh, that truck will be happy after you are done though

 

[~Magick_Man~ 10+ year member]

you need double that port area.
have fun trying to make it fit //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

//content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

i am using a port calculator and for 2 4" ports in a 2 cube box tuned to 34 it says they need to be 26.xx"

is that each?

if it is then that sucks.

because i can fit in up to 14" long ports.

would i be better off with 2 3" instead of 1 4" ?

~Magick_Man~

 

[10W3dodge96 10+ year member]

heh, that truck will be happy after you are done though

Yeah that guy is going to be very happy.//content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[NoLimit 10+ year member]

heh, that truck will be happy after you are done though

//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[~Magick_Man~ 10+ year member]

this should be a little better.

25sq-in of port per driver

~Magick_Man~

 

[10W3dodge96 10+ year member]

did yo use those port tubes on NoLimits box?

 

[~Magick_Man~ 10+ year member]

did yo use those port tubes on NoLimits box?

no i used a mdf slot port on his.

i am trying to stay away from that on this box because i dont want to mess with angling the port like it is on your box.

and i have a ton of 4" pvc pipe so i might as well use some of it.

~Magick_Man~

 

[xluben 10+ year member]

um, what's the volume of the box (after displacement) and how long are the ports?

adding two ports like that (and keeping them the same length) is going to make the tuning A LOT higher (10hz +) possibly.

 

[PatFitz9 10+ year member]

yeah, thats probably not going to work... the port calc is EACH port, so adding more is just making your problem worse

 

[~Magick_Man~ 10+ year member]

um, what's the volume of the box (after displacement) and how long are the ports?
adding two ports like that (and keeping them the same length) is going to make the tuning A LOT higher (10hz +) possibly.

i dont have the exact number yet but i have about 2.2ish per driver after the port is taken out.

i was looking at a single 4" at 11.xx" long which would supposedly give me 34hz with a 2cube box

now i am looking at 2 10.12" long with 2cubes after displacement which should give me ~36hz

i will end up with as close to 2.0 per chamber after the port and sub is taken out.

~Magick_Man~

 

[~Magick_Man~ 10+ year member]

yeah, thats probably not going to work... the port calc is EACH port, so adding more is just making your problem worse

yeah i figured that.

i was using one at 11.xx long shooting for 34hz

now i am using 2 at 10.12 (i think) shooting for 36hz

~Magick_Man~

 

[~Magick_Man~ 10+ year member]

so i guess the real question is will 2 4" ports 10.14" long in a box 2.0 cubes after displacement give me a 36hz tuning?

i am judging this off the port calculator from carstereo.com

~Magick_Man~