box port help

Ok not sure if this is a good idea but I want to try it. Rebuilding the box on my s10 and gunna do a sloted port but out side of the box gunna double baffle the port to get the same radius as an Aero port. The big ? Is I have 7.77 cubes b4 subs using 3 15s rd alpha Max (for now) and have room for only 6" of port. What I'm trying to find out is how many cubic inches of port do I need to have this box tuned to about 75hz.. any help would be appreciated.. if you need more info lmk thanks.

Im not fulling understanding what your asking, but it sounds like you want to know the length your port needs to be to get your desired 75hz tuning, I would imagine your best bet is to look online for a port calculator. normally people do 10-12cubic in of port per cube of air space so in your case you would be looking at 77cubic in of port area, although others would argue you need 100-140 for this although we all know that crap dont matter when competition is involved. Im guessing your saying you have 6inchs of port as in like if you were using a 6inch aero? Either way by the looks of things your just going to have an opening in the box.

http://www.carstereo.com/help/Articles.cfm?id=31

there is a calculator

I have 7.7 cubes box.. I only have 6" of port lenght to play with... say if I had an 8" Aero port I can only go up to 6" high. .. and 52"1/4 length across. .. I'm trying to find out what with would I need to have my box tuned to That frequency.... so port is 51"1/4 X 6"X ? .

I get what you're trying to do... sort of... but making the port 51" long isn't good for much, unless you're thinking Transmission Line. If you are, it's a simple standing wave calculation for the quarter wave length.

The size of the port calculates out to be bigger than the box, for a traditional ported box, though.

Shorten the port, and give yourself atleast 100 sq in. If you can squeeze more area in, s10 boxes typically use 200-300 sq in. Try it out, with a variety of tunings, and see what works. Most likely, the tuning will change by 1 or 2 Hz, but nothing major.

Transmission line??? I'm doing a box for spl. And want to try a Lil different.. I'm doing the basic s10 box subs forward port up. Slotted port.. but I want to try the port out side the box... to see if it gains or losses from the traditional s10 box.. now you get it? LOL Kuz if I was someone else I wouldn't! LOL

well without know sub displacement i cant give you a correct number because im sure they prolly displace at least a cu. ft. of air space if that is what it really is your port needs to be 7.25" long that is using 6.77 as your net cu ft!

Each sub is .31 so .93 sub displacement total..

mrbashful210 wrote:

Transmission line??? I'm doing a box for spl. And want to try a Lil different.. I'm doing the basic s10 box subs forward port up. Slotted port.. but I want to try the port out side the box... to see if it gains or losses from the traditional s10 box.. now you get it? LOL Kuz if I was someone else I wouldn't! LOL

HA! maybe it's still confusing... you said above that you wanted a number for your port volume 51.5" x 6" x ___"

Side-firing, that means your port length is 51.5"... which requires like 400 sq in of port to be practical.

If you meant 20" (box height) x 6" x ___" then I'd say try 2-3".

BTW, don't knock transmission lines. I've heard a few loud ones... but just not in S-10's You need some serious space to rock a TL.

chrisbaldelli wrote:

mrbashful210 wrote:

Transmission line??? I'm doing a box for spl. And want to try a Lil different.. I'm doing the basic s10 box subs forward port up. Slotted port.. but I want to try the port out side the box... to see if it gains or losses from the traditional s10 box.. now you get it? LOL Kuz if I was someone else I wouldn't! LOL

HA! maybe it's still confusing... you said above that you wanted a number for your port volume 51.5" x 6" x ___"

Side-firing, that means your port length is 51.5"... which requires like 400 sq in of port to be practical.

If you meant 20" (box height) x 6" x ___" then I'd say try 2-3".

BTW, don't knock transmission lines. I've heard a few loud ones... but just not in S-10's You need some serious space to rock a TL.

i dont think you understand him he just wants the usual s10 box subs forward port up the 51.5 x 6 is his port area so he has 309 sq in of port he wants to know how long to make the port outside the box instead if inside the box which with what he has said his external port should be like 7 inches! so that is what i come up with to get you tuned to 75 hz!

^^^^^^^^ yes! !! Buuuttttt.. LOL the 6" isn't the with its the Max height I can go.. you have me at 7" high and 6 is Max.... and 51" long..

so what is the actual opening of the port? and can it be changed any? to get to 75hz it has to be 7" with those numbers a 6" came out to 78 hz

if you do it 6" deep and 49" wide then a 6" external port will give you a tuning frequency of 75.8 thats what i can come up with with out having all the variables i made the sq in of the port smaller to accomodate for the shorter port length. does this make sense?

poundstone wrote:

so what is the actual opening of the port? and can it be changed any? to get to 75hz it has to be 7" with those numbers a 6" came out to 78 hz

Yesssss its the opening of the port that I need changed... but just the port length has to be 6" ..... so it doesn't pass window line.. and 51" across sloted port(basics10) .....

ok if you wanna keep the 51" across you need to make it 51"wx5.5"dx5.5"L for your port! just take a half inch off and make the port 5.5" tall and that will give you a tuning frequency of 75.66. that is what i can come up with

just to make sure the 51" is the inside of the port measurement right?

PERFECT!!!!!! YEAH ITS 51" inside. 52.5 outside. ...thanks for putting up with this grand design LOL... ill post how I did with it in bout a week...

k no prob let me know how it turns out!

You'll be the first to know....... thanks