Box for 2 sa 12's feed back

[CleanSierra]

The divider between chambers is all the bracing you probably need. A shelf brace that touches all 4 sides of the box is strong as hell. The dowels won't be needed at all.

P.S. I know Kranny is just being funny

[bmxscion]

If your concerned about one sub being already broken in and the other brand new, just swap speakers in your single box break in new sub, then take the advice here and build a new box.

[Joe X]

wow thanks for all the help john i really appreciate it. one problem i have is that i bought an sa 12 a few months ago and i bought a newer one recently. therefore i need a new box and i didnt want to do shared because i am scared it will mess up my newer sub. would it be ok to put an old sub and a brand new one together like that in the same chamber? on top of that i already bought 2 4'' aero ports. i also dont have the skills to do 45 corners or flared slotted ports thats why i strayed from slotted. if it will make a significant difference doing subs and port on the same face i will have to do a slot port.

As said don't run subs up in a trunk car, you would need 3 4" aeros for proper port area, also you don't really need any 45s or flares, you just need to round any inner edges of the slot port.

Also as said you can run your new sub on the old box for a week and that will likely be enough for break in if you are concerned.

[Nealon14]

what would happen if i dont have the right port area? thats a good idea i will run my new sub in my old box for now

[Joe X]

To the very least your port output will be reduced at higher volume and some overall efficiency is lost, 2 4" ports is about half the port area needed, ideally 55-60 square inches of port area can be given to a couple of those subs.