View Full Version : port lenth help! got all other dimensions

mac bleeze
01-06-2005, 01:02 AM
first off thanks to bcarpenter for helping me with the box design... we came up with 31x15x16 widthXheightXdepth for external box dimensions for a ported box. widthXheightXdepth... we also got the vent size of 2.75 x 13.5 and are tuning is somewhere around 32 hz. the thing we cant figure out is the port length.. we came up with somewhere around 40-45". After that he could no logner help me. another thing i dont kno how to put 40-45 inches of port lenth. 31+16 equals 47 and yea not sure what i would need to do.. ne help or pictures of there port length..; im not sure what port lenth really is. i do but a very vague idea from what my jl audio specs sheet tells me. so if u can please help. my aim adress is bigjonny33 if u want to im me there.

01-06-2005, 10:00 AM
Please try to make your posts a lil more legible. Puncuation is not very hard.

If You are running .75" mdf walls & .75" MDF slot port with a common wall then I have your results as follows:

Gross Volume: 3.342 (31x15x16 external = 29.5x13.5x14.5 internal).

You didn't give woofer displacement.

Port area of 37.125 sq in. with a length (straight) of 40" you're tuned to 31.4hz with a net vB of 2.252 cubes.

To tune to 32.02hz - You'd need 36.5" port length.

You'd have to run a "labyrinth" port:
1st board 13.25"
2nd board 12.5"
3rd board 5.75".

Good luck