placement of ports in a box

[Autruche]

I'm no pro, but I'll try to answer your questions to the best of my abilities.

alright that makes sense. so for this loading wall when you say behind the sub do you mean behind the motor? how do i determine which side is behind the sub?

Yep, you put the wall behind the sub's motor. Basically it'd be something like a 10 inch wide piece of wood that you'd want to put a couple of inches behind the motor of the sub, parallel to the baffle.

also how do you determine what is too close to the internal port?

As long as it's a couple inches or so farther away from your internal port opening that your port is wide you shouldn't really effect the tuning of the port. So say you have a 5 inch wide port, if you can keep the loading wall more than 7 inches away from the port opening then the tuning should not be effected much.

how do you know if one of the subs is unloading will it be moving more than the other?

Yes. The sub that is unloading will be stuck in a lower pressure section of the box, causing it to lose cone control and reach it's mechanical limits easier.

when designing a box is there any key giveaways to determine if there will be any unloading issues?

Generally you have no concern about it in a 1 or 2 sub setup, unless you play way below your tuning. The time when it is most likely to occur is when you put your subs in rows of 3 or more. Here's a quick sketchup I did as an example for you: http://i172.photobucket.com/albums/w36/tha_ostrich/312sunloadingissuesbox.jpg

[will77530]

cool thanks a lot man that really helped

[jakobebassbudds]

Generally you have no concern about it in a 1 or 2 sub setup, unless you play way below your tuning. The time when it is most likely to occur is when you put your subs in rows of 3 or more. Here's a quick sketchup I did as an example for you: http://i172.photobuc...ngissuesbox.jpg

hey that looks like mine lol and yeah cuz of the low tunning and the fact that like Autruche said its a row of three with 1 port like the pic and if i put a piece of wood behind motor i would loose displacement

[fecupe2001]

Nice explaining mate!! I do have to disagree with you in a small thing, yes you can see it sometimes on 2 12´s boxes lol, a friend of mine had a corolla with 2 12s with something like 40" wide box lol, he placed one of the subs way to far away from the port and that thing sounded like crap, i had to do a loading wall just like you are saying and problem solved, but anyways, yeah it happens a lot hehe