Need help on Box Design

[Dtrain]

So I've been lurking around this site for awhile now, and I figured it was time to register and actually make a post about my new box. I'm looking to build my first ported box, to go in my 01 Toyota Corolla, I have two Alpine Type R's 4Ohm's, and a AudioPipe 1500 to go along with them.

I'm thinking I need to have 2CF for each sub and a tuning frequency of about ~35Hz would be what my Type R's would need for me to get down to business. So far I've calculated my box needs to be around using MDF 3/4 of course.

Height - 14

Width - 18

Length - 36

And I plan on making one port on the box, I'm not exactly sure about my Port settings, but this is what I came up with.

Height - 6

Width - 4

Length - 4

Diameter - 4

Since this is my first box I've ever made I'm kind of worried about messing it up and looking for pointers or wondering if the dimensions I came up with any good for my new system. And of course thanks.

[6berry]

try downloading torres box calculator and itll make everything so much easier! your port is the only thing that looks wrong to me. first it can be 4 wide x 4 high x 6 long x 4" diameter and you need way more port area

you should make the box dimensions bigger to account for port and sub displacement and then try to get between 12-16 sq in of port area per cubic foot of box. all of this is pretty self explanatory when using torres calculator

[RAM_Designs]

Your port is too small. With the dimensions you listed, you only have 4.12ft^3 before sub and port displacements. If you want 4ft^3 after displacements, using a slot port, you're going to need around 5-5.5ft^3 depending on the size and tuning of the port.

[Dtrain]

Thanks for the quick replies guy's, so I downloaded the Torres Speaker Box Calculator. I've Been toying with this Calculator for a hour or so now, and one thing I think I'm still doing wrong is, I'm still not sure about is what my size port should be. As of course I can make the box bigger to compensate for my box port, but my question is, I now have the box at 14high x20wide x 40long while my box port is 5wide x 8high x 5long x 5diameter which gives me a 5.09ft^3 and a 34.65Hz frequency. Since I made my box bigger is my port still too small?

[6berry]

you still cant use square and circle dimensions together but yes that port is still small. look at the right side where it says port area range and try to get your port area in those dimensions.

[Dtrain]

Ok just to ask a question to make sure I'm doing this right man. My port range area is 46-67, with my above settings, what exactly do I need to apply to get my Port dimensions to match my range area, I'm not exactly understanding that one.

[6berry]

if you are using a circle port like a pvc pipe or aero port then enter 1 in # of ports and enter the diameter of the port in diameter. if using a slot port then enter dimensions in the height and width. use that to find the port area and then from there enter lengths until you get the desired tuning

[Dtrain]

Completely understand you now I was doing a mixture of it all wasn't thinking that clearly through, I completely see what I was doing wrong as of now. So basically just mess with the port dimensions until I have my desired Frequency and CF. I just got to find to make a bigger port, but Thank you man for helping me with my box.

[Dtrain]

Fixed it up a little bit this is the final product so far, as of now that is.

Box dimensions are 16 x 20 x 40, while my port dimension are 14.5 x 4 x 19.

That gives me ~35Hz and 5ft^3 before displacement. And after adding my Common Port Wall, Woofer displacement, and leaving Bracing displacement blank(Not sure how to calculate this one so I left it blank), I ended up with 4.88ft^3 and 35Hz. Last two questions are how do I calculate bracing displacement, and also should I be trying to go for 2CF per sub or 2.5 per sub, as I've heard both sound great.