Sub and port locations?

[RooTxBeeR]

Ok well from my knowledge, whichever side the port is on, its usually best to have the sub on the opposite side of that. I am doing a a build of a 9515 in a trunk of a Challenger, facing the sub to the trunk and porting into the cabin. The dude wants to know if keeping the sub in the middle would effect it if he wants to do 1 port on a side.

[philrab]

Hopefully someone more experienced will chime in, but my big concern with subwoofer/port placement is always the sub loading directly into the port. That can and does usually cause issues. As long as that isn't occurring (ie, the sub's magnet is facing into/towards the port) you'd probably be okay. Can you post a sketch of the box you have in mind?

Last enclosure I built had the sub all the way on the left hand side of the baffle, port going out the right side face of the enclosure. The port was 90 degrees to the sub, haven't had any issues.

[Joe X]

Sub needs to be reasonably away from the inner end of the port, that's really important.

[RooTxBeeR]

The top left is port, bottom right is sub, would having the sub in the middle of that baffle make a difference? I want to try and get 2 ports, one on either side with sub in the middle, but he wants one big ass port on the side.

[thefourth]

The top left is port, bottom right is sub, would having the sub in the middle of that baffle make a difference? I want to try and get 2 ports, one on either side with port in the middle, but he wants one big ass port.

I've pondered this myself a few times. Tuned for some answers

[hispls]

At some point you're splitting hairs about sub and port position on the box. Some changes will be audible, most will not. From my experience using the same box but just changing the position of the woofer on the baffle was a few tenths of a dB which is definitely inaudible. Now keeping port far enough away from obstructions seems more dramatic as does which direction you aim it, and if you fire sub or port back, distance from the back of the drunk can be noticeable. Assuming same power and subs, I've never personally got more than + or - 1.5 dB by just changing the direction of the port or position of subs on the box (this is assuming a daily/music type application)

Other fundamentals are more important IMO, like having enough clearance around each opening of the port, having plenty of port area (and decent ratio of width to height), adequate thickness and bracing to prevent any flex, and of course tuning to the sub and your tastes.

[RooTxBeeR]

Yeah this is taking into account that everything else is set and in a good position, just wondering what the ultimate difference would be between the pic i posted, and then the same thing with the sub just in the middle. But, I need more port than a 8" aero can give me, and that's fucking huge. So I might end up having to do dual ports regardless.