View Full Version : (3) JL 15w6 speakers in a civic with 7.3 cubic feet... what size port?...

11-14-2006, 10:18 PM
Hi, i have a design for (3) JL 15w6's in a 7.3 cubic feet box. It messures 15hx32dx32w. I am going to put these in a honda civic to fit perfectly. i went to http://www.carstereo.com/help/Articles.cfm?id=31 and used the port calculator and entered in all the specs of the speaker and it came up with 7.38 as the length of one side of the port. how do i build this because i've never built a ported box before, but have built several sealed boxes.The speakers specs are as following:

Fs: 16.3hz
Qts: 0.312
Qes: 0.325
Qms: 7.817
Vas: 10.88 cubic feet
Xmax: 10.7mm
Efficiency: 87.9db
Sd: 131 inches squared
Re: 10.88 ohm
Znom: Dual 6 ohm
Pt: 400 watts RMS

I entered all the information from this list that applied on the calculator and got that, if i'm doing something wrong, someone tell me. Here is how the box is going to look and where i want to put the port. If i have to, i'll put another port on the other side.


let me know what you guys think and help me out with this port!

11-15-2006, 09:25 AM
also, i wanted to put 1" pegs all the way around the box so i could take out my spare tire and face them down. How would that sound? My brother's f-150 has 2 10's facing down with pegs and they hit hard so i was thinking that maybe it would be the same. let me have some feedback and some ideas from you guys and if i face it down, should i port it? let me know.

11-15-2006, 09:26 AM
15 sq in of port per cubic foot is the rule of thumb

11-15-2006, 09:43 AM
so i would need 109.5 sq inches. how big would i make the port? i remember asking a local speaker shop a while back and he explained to me about sq inches and dividing it and whatever you get you make the box by that area... maybe?... like for instance if it's 100 sq inches, you would make the port 10"x10"? i dunno someone elaborate for me, thanks.

11-15-2006, 09:50 AM
Yes, height x width of the port is the port area. The length of the port will be determined with your tuning preference.

11-15-2006, 09:59 AM
how many hertz do you recommend for the 3? so i can plug that into the calculator. Since its 109.5 sq inches, i plan to make the port 15"x7.3". Now i just need the length to an appropriate hz that hit low and hard. let me know how everthing sounds so far and help me with how many hertz to tune it to!