Running into a problem. Suggestions Appreciated

[holley2346 6]

I am going the wall route and am in the designing stages to make sure everything is going to fit. The issue I am having is with my ports... I can get my tuning around 35 which is where I want it when there is only 4 inches ^2 of port per square inch but I know that is WAYYY low. When I get my ratio of port in^3 to box volume right my tuning ends up in the teens.... what can I do?

The dimensions I'm going with are 48 inches wide, 36.5 inches tall, 33 inches front to back. I just need some help with tuning... this is going to be a daily heavily demoed setup.

edit** and the port in this picture is 17x8 which is about as big as I'm going to be able to go. And this setup is for 4 18's.

Thanks for the help!

Edited March 24, 2011 by holley2346

[sefugi 166]

Let me first say that I am not a box designer. With a 17x8 port that is only 136in of port, which to me is not enough for 2 18's. For 4 I am thinking you will need at least 350-400, I may be way out in left feild and maybe someone will chime in and correct me.

What lenght are you planning for the port?? With the specs you gave and no scetch it seems it is just a slot without a actual port.

[Sir-Lancelot 216]

136" of port is not going to work out like you want.

Why not try aero and see what you can get or hit up one of the box designers and see if they can work up something.

[S.DeYoung 967]

Thats definitely not enough port area. I have two 18" Xcons and 240" of port area. That port will not meet up to your expectations.

Is there another way you can align the subs so you can get more port? What are the dimensions of the baffle?

[///M5 2,833]

When I get my ratio of port in^3 to box volume right my tuning ends up in the teens.... what can I do?

Shorten the port. That is the opposite problem everyone else has, although once you compute the area you actually need that will take care of it as well. Drivers, power, box size are all required to calculate port size. Then just pick a size that keeps the air velocity reasonable.

[holley2346 6]

When I get my ratio of port in^3 to box volume right my tuning ends up in the teens.... what can I do?

Shorten the port. That is the opposite problem everyone else has, although once you compute the area you actually need that will take care of it as well. Drivers, power, box size are all required to calculate port size. Then just pick a size that keeps the air velocity reasonable.

Everyone misunderstood my question.... im limited on the width and heigth of my port. Using the maximum dimensions my port would have to be 1 inch deep to have reasonable tuning but that makes my sq in of port close to nothing..... But when I get my sq in of port correct the tuning is in the teens.

[S.DeYoung 967]

When I get my ratio of port in^3 to box volume right my tuning ends up in the teens.... what can I do?

Shorten the port. That is the opposite problem everyone else has, although once you compute the area you actually need that will take care of it as well. Drivers, power, box size are all required to calculate port size. Then just pick a size that keeps the air velocity reasonable.

Everyone misunderstood my question.... im limited on the width and heigth of my port. Using the maximum dimensions my port would have to be 1 inch deep to have reasonable tuning but that makes my sq in of port close to nothing..... But when I get my sq in of port correct the tuning is in the teens.

square inches only applies to the width x height. Not the depth or this would be cubed inches. A general rule is 12-16 inches per cubic foot. My port is 6"h x 40"w = 240".

[holley2346 6]

When I get my ratio of port in^3 to box volume right my tuning ends up in the teens.... what can I do?

Shorten the port. That is the opposite problem everyone else has, although once you compute the area you actually need that will take care of it as well. Drivers, power, box size are all required to calculate port size. Then just pick a size that keeps the air velocity reasonable.

Everyone misunderstood my question.... im limited on the width and heigth of my port. Using the maximum dimensions my port would have to be 1 inch deep to have reasonable tuning but that makes my sq in of port close to nothing..... But when I get my sq in of port correct the tuning is in the teens.

square inches only applies to the width x height. Not the depth or this would be cubed inches. A general rule is 12-16 inches per cubic foot. My port is 6"h x 40"w = 240".

Ohhhh okay I understand now... well looking at the picture what can I do? That's what I have to work with.

[S.DeYoung 967]

What are the dimensions of that baffle and what kind of subwoofers? The BTL N2's?

nm I just saw you posted the dimensions

[thor02 2]

If there's no way to do a traditional port, i'm thinking a clamshell design could work. Just throwing that out there.

[holley2346 6]

What are the dimensions of that baffle and what kind of subwoofers? The BTL N2's?

48 wide 36.5 inches tall.... btl n2's. ill arrange em however I need too as long as I can get it set up right for a daily ground pounder setup that will be metered.

[holley2346 6]

If there's no way to do a traditional port, i'm thinking a clamshell design could work. Just throwing that out there.

I hadn't even thought of this.... that's a great idea. I've just never designed a clamshell before.

[S.DeYoung 967]

I wish they could stack on top of each other and you could make one big port down the middle. But if they are like my xcons the cut-out diameter is 16.75" and the outside diameter is 18.5". Which is a little to big of course. I will do more playing around with the numbers.

[holley2346 6]

I wish they could stack on top of each other and you could make one big port down the middle. But if they are like my xcons the cut-out diameter is 16.75" and the outside diameter is 18.5". Which is a little to big of course. I will do more playing around with the numbers.

If you do designs I will gladly send a few bucks your way for throwing something together for me... if there is absolutely no possible way I will have to do a clamshell I guess.

I would GREATLY appreciate it...

[Goldtaz1 4]

Get rid of the second row seats and you'll be able to have the right box in there. Who's gonna build it?? Matt? What happened to doing the 6 15's? LOL!

Edited March 25, 2011 by Goldtaz1

[///M5 2,833]

Shape doesn't change a box, slant the baffle and increase its size and you are golden.

[Quentin Jarrell 671]

^^^^^^^ slant it just enough to put the subs on top of each other with a port centered, top to bottom

[holley2346 6]

^^^^^^^ slant it just enough to put the subs on top of each other with a port centered, top to bottom

I considered doing this but just don't want a crooked wall... I'm trying to draw up a clamshell since everyone I've asked doesn't do clamshells or walls. So I'm trying to figure this out myself. I even contacted a couple of paid box builders to no avail.