Subwoofer Box

[gbodybuick]

Hello all. Im trying to figure out how to get 2 15's in the back on my 80' century 4 door. I want to have two 15's (American Bass Hawk 15) and im having trouble finding a box for them. The thing with 15's is they just fit in a g body trunk, and finding a custom box is very difficult. To make it work, it would have to take up the back deck and come out and cover most of the rest of the trunk. I'd consider just building a box on my own but I have no idea what I'm doing, although it might be possible if I had the right mesurments for the car and tuning of the subs. Any ideas? I know allot of you will say to go smaller, but I just gotta have the 15's.

Also, some of you might know me from the help forms when my car wouldn't run, turned out it was the fuel pump, runs like a champ now!

 

[Drkuhar]

I found a company online called ak audio that made boxes that were notched for the rear deck speakers and trunk spring , set in the ledge and stuck out and dropped down to the trunk floor . They had them for 12 and 15 but they were pricy. Looked nice but pricy. Lots of options. I just built my own

 

[gbodybuick]

I found a company online called ak audio that made boxes that were notched for the rear deck speakers and trunk spring , set in the ledge and stuck out and dropped down to the trunk floor . They had them for 12 and 15 but they were pricy. Looked nice but pricy. Lots of options. I just built my ownView attachment 239658

Iv seen them. They look perfect but not enough box area for the power im gonna push (3k rms).

 

[Sweet_Johnny]

I hate to say it but I believe you're either going to pay big $$ for a good custom built setup or jump in and do it yourself. You'll need to know the sub's required box size for sealed, ported, or bandpass boxes, as well as the port size and tube length to achieve the proper frequency if not going with a sealed box. Websites like subbox.pro and speakerboxlite.com are very helpful in getting the dimensions right. Also, with 15s you can't cheap out on the MDF and should use absolutely no thinner than 3/4", but plywood is better in this situation simply due to the strength. Either material would need to be internally braced.

 

[gbodybuick]

I hate to say it but I believe you're either going to pay big $$ for a good custom built setup or jump in and do it yourself. You'll need to know the sub's required box size for sealed, ported, or bandpass boxes, as well as the port size and tube length to achieve the proper frequency if not going with a sealed box. Websites like subbox.pro and speakerboxlite.com are very helpful in getting the dimensions right. Also, with 15s you can't cheap out on the MDF and should use absolutely no thinner than 3/4", but plywood is better in this situation simply due to the strength. Either material would need to be internally braced.

I see. I have no idea how to do any of that. I could build a box but I can't figure out the proper tuning/port length/etc. Might have to tap out on this one.

 

[Sweet_Johnny]

I see. I have no idea how to do any of that. I could build a box but I can't figure out the proper tuning/port length/etc. Might have to tap out on this one.

If you can build a box then you're fine- the websites do all the math for you. Basically, if you can input the speaker stats and your desired goals it'll tell you everything you need to know, though sometimes you have to play around with the numbers to get what you want. You'll need to take measurements of your trunk, but MORE than a basic height/width because there are other things that get in the way. Measure the height available on one side then slide the tape measure across to the other side to see if it hits anything along the way. Same goes for width, and measure diagonally too.

Looking up your subs will net you their frequency response range which tells you what your low and high pass crossovers should be. Yes, blocking low frequency below your subs ability is necessary or it struggles to reproduce sound that it can't. You'll also find what the requirements are for the various boxes- X cubic feet for sealed, X for ported, etc.. That is the box size that will get you the best response from the subs, then you can tune the ports for a specific frequency (I like about 34 Hz for my 12" ported box) and the websites tell you the size and length you'll need.

Here I was playing with putting three 6.5"speakers in a box (per side) that would fit flush with the floor behind the seat in my El Camino. It was a mix of 2 subs and a full range speaker in each box that would aim up and the port would be directed under the seat. As I changed the external dimensions the website altered the port design accordingly.




All you really need to know to get going is the specs on the subs, the space you need to work within, and the frequency response you wish to achieve. Keeping in mind that 15s are heavy and need to be as secure as any other load you've ever hauled.