Box design help

[KoolDrew 0]

This is my first real system and I plan on running 2 10" FI Q's with a Sundown Audio SAZ-3000D. I have plenty of experience with woodwork, but since this is my first real system where I'm building my own box, I need some help with that.

First off, originally I was planning on facing the subs inside the car and seal off the rest of the trunk. It's a 4-door and I can't really remove the back seat, but the majority of the time the back seat is down anyway. However, after reading a bit more I've heard a lot of people mention and tests done to show the subs may actually be louder facing the rear of the car. What do you guys think the optimal setup in my car will be? I'm driving a 2000 4-door sunfire. Also, if I do face them towards the rear is it still a good idea to keep the seat down?

I know the max recommended for two 10" FI Q's is 2.4 cubic feet. I plan on building a box around there. However, does the recommended take into account port volume or driver displacement or do I have to take that into account myself? If I build the box 30 inches wide, 13 inches high, and 18 inches deep with two inch wide ports on each side (two ports since I'm splitting it into two chambers, one for each sub) I'm assuming that would give me 2.69 cubic feet without driver displacement (but taking into account wood thickeness, 3/4" MDF). With displacement it would bring me down to 2.45 cubic feet, a bit less if I take into consideration that it's split into two chambers. So I think I have box size and dimensions under control?

The problem I have is port width, length, volume, etc. I plan to tune at 32Hz since I heard this was optimal. I was also recommended to do 15 square inches of port per cubic foot of volume. So how big should each port be?

Any input? How wide do you think the ports should be? If it were 2" wide, I'd do 9" long, 1.5" wide, 12" long, or 1" wide, 18" long?

Edited January 11, 2008 by KoolDrew

[saltybeanbag 0]

i dont think you have to divide the box or go with a dual port but thats all personal pref. when it comes to box building and design. the sundown saz-3000 can deliver some power so you want to build the box optimized for power handling. if it was a one chambered box id do 3.5 cubes (not counting port yet but counting sub) and 12x3x36.5 deep port which is a pretty deep port and is going to "L" inside the box. with the power you're running sealed is a nice option too.

[Fi Car Audio 64]

Running separate chambers eats up more internal volume (divider and extra port board thickness). Now if it is for aesthetic reasons and symmetry, then I understand running dual ports, but you will still have to use a slightly larger enclosure to do the same thing.

Single slot port with a pair of the subs in a common chamber will work well. You are at 3.13 cuft before port and driver displacement... With a single 3" X 11.5" port that is 32" long you will be tuend to 33Hz and have a solid daily driver that will hit deep and hard.

Thanks,

Scott