SPL only box for alpine swr12's

I want to build a box for MAX SPL only with 2 Alpine swR-12's

I am currently running a common sealed box on them and occosionaly enter spl drags. I hit upwards of 143 with the sealed box and an alpine mrv-1507. Any chance of getting to 150 in a jeep cherokee without changing to diff subs or amp??

So i guess my question would be-- what dimensions of box should i build - Size doesn't matter as the box is just for SPL and would be changed out for daily driving / SQ comps??? (mabee)

Well a vented enclosure could give you a 3 db gain....

Problem is that I don't think the SWR-12's are made for a vented enclosure.....not that it couldn't be done...It will just take a lot of math and precision to do it....and I'd be glad to help you with it, if you wanna attempt it...

A bandpass would also give you a DB gain.....but, it's a huge enclosure and, well, the frequency range it has...sux.  so for SQ I wouldn't recommend it...

The vented also has it's limitations as far as SQ go, but can be worked with a lot more than a bandpass....

But overall, if you don't wanna get new subs or a new amp....you'd probably have to go with a vented...of course this is if the sealed enclosure you currently have is built to the theile-small specs of the subs in there....if it's not...try that first...

Go for a ported box and the most important thing to consider is the port tuning frequency. Find the frequency that your Jeep and the subs produce the most SPL from and make a port to reflect this freqeuncy. You have a parametric EQ on the 1507 that you can boost a single frequency so make sure that frequency is what the port frequency is and your set.

Thanks for your help...

ok to start with... the sealed box is probably not built to the theile small perameters, as it was an off-the shelf box. Where do i find all the info about my subs that I need for the theile-small perameters??

As for frequency, in the sealed box i have now, it hits at 51hz, is that what i tune the ported box to??