I just purchased a infinity 10 inch kappa sub and want to get a box built before hand. Problem is that I SUCK at geometry and was hoping someone have their specs online. Please help

 

MTX Thunderform.

 

dang it tampa, stop thinking like bulldog! he already suggested that :-P but I already purchased the stuff and don't have the cash to run 2 subs.

 

Sounds like we have a project in common, I just finished up one Kappa Perfect 10" sub and am working on the other. I wanted mine to be centered exactly behind the seat, which meant some strange angles where the back wall changes to the plastic on the side, plus there's that little ledge that runs the width of the back wall. So here's what I did- I cut the first pieces to match the floor and back wall, then the top and front keeping in mind that the slope of the front was to match the back of the seat and making sure the speaker magnet was at least 1/2" from any surface. The clever trick is to build it much wider than you will need. Then I measured all the inside dimensions and put them in a spreadsheet and added a few calculations to find out exactly how wide it should be to give me the exact recommended cubic feet. Then I just trimmed off all the extra and put the side on.
I am extremely happy with the results, the first one all by itself kicks damn hard.




(waiting to finish the other sub before I tackle the final wiring)

I covered it in a gray vinyl that almost matches the truck interior. It's very close to the soft part of the center arm rest. The speaker is actually bolted to the metal trim ring then set in the box flush with the surface.

 

Mark would you happen to have the dimensions? pleaseee?

 

The problem is I'm not quite sure how to describe the dimensions. There are some weird angles and round parts.

Which Kappa did you get? Does it have the same 0.6 cubic-feet specification?

 

it's the Kappa, not perfect. And it sure does require the same .6

is there anyway we can talk? like email, aim or ICQ?

 

You're in luck, I found my original printouts in the garbage. I took pictures of the first box then printed them out on 8x10 and drew the dimensions on them so I could make the second one. I'm putting the dimensions on the original images now and will post them in a bit.

Check the dimensions of the Kappa vs. the Kappa Perfects (their web site might have them). If they are any deeper then you will have some redesigning to do, the boxes I made don't leave any room for larger magnets. I suspect they will be ok though, since the Perfects are supposed to be their ultimate sub and probably have the largest back-end.

 

the perfect requires a 6 inch depth and 9.10 diameter cut out
the kappa 5.07 depth and 8.88 cut out.

I really appreciate this

 

Boxes can be hard to make. If you have the dimensions, it makes it a lot easier, and Mark yours looks great. Problem is, if you're making it without any dimensions beforehand, you have to have perfect geometry. There can't be an inch of space that isn't air tight, or you aren't going to have very good output. If it's all sealed in good and there is no air coming out, you're in good shape. Problem is, when you find you have a leak, your box is already made......

 

Here are the dimensions for the passenger side box. (And yes, I did actually measure down to the thousandth of an inch).

Note: these dimensions are for 3/4" MDF. So any edges you see that aren't marked are 0.750". This probably isn't the perfect design or easiest to assemble, because it was made by measuring and cutting each piece one at a time without any design on paper. Building the second one I realized how it could have been made easier, but I didn't feel like mucking around with the dimensions.
If you mount the speaker like most boxes where the speaker screws into the front (sticks out, not flush), then the interior volume will be slightly larger, but I don't think enough to make a difference.



While the measurable front height is exactly 13.000" (a fluke that it came out even), the actual piece is about .35" larger because of the hidden part of the angled cut at the top.
I didn't include the dimensions and placement of the hole because it will depend on how you mount the speaker. When you find the center point for the hole, cut it .386" lower. That will result in the magnet being centered between the bottom and back (found that one the hard way by trial and error).


I don't know how wide the tall back piece is on the right side (not the far right edge piece). It follows the angle cut out of the bottom all the way to the outside edge. The far right piece is a facade only, glued to the back one. No dimensions on that one either. Once the rest of the box is done, put it in place and use a piece of cardboard to make a template to follow the plastic trim in the cab and cut a strip of MDF to fit to the back.
You can see how some of these back pieces are joined together on the inside in the first picture.


The 3.626 is measured on the top side, while the 4.306 is measured on the inside/bottom side.
The lower right corner (top right back corner when sitting up) was slowly sanded down until it matched the contour of the cab interior trim.

 

"Your post includes too many images", whatever...
Part 2


The front of the box is at the top. The holes are for the screws that held down the CD changer. I don't have any dimensions for those, but once I'd cut the bottom, I simply put it in place and tapped it with a hammer to mark the positions. Two of them are sealed off, and the other two are being used to hold the box down.


The back edge doesn't exactly match the cab interior like the other side, but it will be hidden when I'm finished. If you want it to match, you could cut it a little wider then sand/file it down until it fit just right.


Yeah, I know it looks like crap - that's a bunch of putty filling the seams and screw holes that I hadn't sanded down yet when I took this picture.

 

Mark, thank you for the great instructions. Just one more question, did you use poly fill?

 

Yep. About half a bag each. Though I don't remember how much is in a bag, so that probably didn't help.

BTW, I used a router to cut the whole thing. Much more accurate than most other types of saws.