View Full Version : Please help me with ported box question for my Type X 10!!

10-10-2007, 02:36 PM
So Alpine's recommended enclosure for a slot port box is rectangular and the port has a 90* angle in it, and is a certain length and area. Well, I am designing a box that will fit in between the center console and the back seat of my 2005 F150 supercrew, so obviously the dimensions they call for won't work. I've seen the thread about all the different sized boxes tuned to different frequencies, but they are all that exact same shape. What I'm curious about is how I would build a slot/regular ported box that has to be somewhat of a strange shape, and still know where to put the port, how long to make it, etc? I think the inside of the enclosure will still be somewhat rectangular but may have one slanted side. Is this okay? Also, I've noticed with slot ported boxes that the slot is always on the same face as where the woofer mounts. Is this always necessary? I may downfire the sub, but have the slot on the side, etc. If someone could point me in the right direction, I want to stick with Alpine's specs as much as I can, unless someone has a better suggestion.

Short version: As long as the overall volume inside the box is the same, and the overall displaced volume and area of the port are the same, does it matter where the port is, if the port exit is on the same face as the sub, or what shape the box is? Thanks guys!


10-10-2007, 02:58 PM
"Might" not be ideal, but it'll work and if that's all you can do then it's better than nothing...

10-10-2007, 03:02 PM
This is sort of what I'm talking about. The sub is firing down (obviously it will be on pegs or something to hold it off the ground) and the port is exiting on the side. So rather than a "top view" this would be a side view of the box as it will be installed. Will this work as long as all the end measurements are the same or does the shape affect the tuning? I just don't want to bottom the sub out.

My crude drawing in MS Paint: :D

10-10-2007, 04:39 PM
Port area, port length, and enclosure volume after port displacement need to all stay the same for the enclosure to have the same tuning.

10-10-2007, 04:59 PM
But other than that, I'm fine? So if Alpine calls for a 1.3 ft^3 box before port displacement, I don't necessarily have to use their dimensions to get there right? So instead of their 18x12xwhatever, I could do inside dimensions of whatever I wanted, as long as I pulled 1.3 out of it? Same thing with the slot port area- it calls for 12"x1" slot port. Could I accomplish the same thing doing one that was 6"x2"? And does it matter where in the box the port is, as long as the area and net volume end up being the same?

For those that have or have had the Type X 10, do they tend to work better in sealed or ported? And at what box volume? Based on the box I built for my Kicker CVX 12 in the same location, I'd say if I upfire, either way I have just over 1ft.^3 to work with.