Well Im picking up some Audiobanhn 12's subs off a friend. 800W Max each. And I got a box free, from a friend that would fit. Now, It does not have a Port. Would one be needed for best sound quality ?
If so, how could I go about making one, just drilling a 4 inch hole ?

 

More information is needed. What size is the box, what are the T/S parameters of the drivers? If you are concerned with sound quality you might just want to stick with a sealed set up; they are easier and smaller. If the box is prefabricated, you should throughly inspect it, see what thickness it is and what kind of bracing it has. If either of these are lacking consider building your own. As I mentioned earlier sealed boxs are pretty easy to construct and will most likely be better than a prefabricated one. Best of luck with your new system!

 

Ports are not just holes....A ported box is carefully designed with the Thiel-Small parameters of the woofer according to scientific principles. It has a specific diameter and lenght to resonate with the box at the correct frequency depending on the woofer.

think of a woofer and box as the suspension of a car...You cannot just add any old springs and shockabsorbers and expect race car performance. Too weak and you bottom out and wallow all over bumps...To stiff and things break.

I "general" sealed boxes are smaller and easier to build for good sound quality. Ported boxes are larger and can go to lower frequencies...But neede greater care to design and build properly....Those are the basics and I am sure that experienced box builders will come up will all sorts of other details and exceptions...

best bet for a novice is to go to the website of you subwoofer and get the sealed or ported box recommendations.

 

Are ports needed well YES.

 

Ah alright. Box is 4ft long, 20 inch high and 18inch deep. Box thickness is aprox 1 inch thick. 2 holes for my 12' subs I am recieving in a few weeks. Is this any more help ?

 

No, it is not nessecary to have a ported enclosure to have great sound quality. Trying to modify an exisitng enclosure from sealed to ported will most likely yeild shitty results. Try out the box you have now, if you don't like the sound, or if you want more low-frequency response, then consider building a new box from scratch.

 

That's not a box... it is a coffin!

I am curious why the box is that big and that thick. This goes back to the previously mentioned Thiel-Small parameters of the woofer. I have not heard Audiobahn drivers needing such a large enclosure

 

I have a quick question on this topic. I have a Bass Slammer dual 10" sealed enclosure with 0.75 cu ft. per chamber. I have a Sony Xplod XS-L103P5B sub that calls for a 0.78 cu. ft. for a ported box. I was wondering if I could turn one chamber ported and leave the other sealed. I'd like to get or build a proper ported box but I don't have the time or the money. Would this work and sound good or should I just leave it the way it is. I don't mind the way it sounds now, but I would like it to be a bit louder.

 

thats huge dude are YOU gonna port it yourself? that would make sence..

 

Eeek. Got the measurements ubber wrong. 36inch long. 3ft. 16inch tall. and abou 8inch backspace/deep.
The box is like this shaped.

|-\
|__\ -Subs sit there.

Maby I will just keep with the sealed unit.