View Full Version : How does everybody feel about a shared port

01-16-2008, 11:03 AM
for 2 subs? I need a small box and I am willing to live with lower output and some peaky sound. I am trying to think of ways to maximize volume, output and everything. This is for a daily driver (I drive a lot for work) and I just like to slam it every once in a while. I am not a SPL guy.

I have a pair of T2 12s and I can go with a box about 34x14x14 or so. I was considering a 3" slot port on one end for both subs. This is about half of the recommended size.

Is this a disaster, or will it be OK for my situation? Any other suggestions are welcome as well.

01-16-2008, 11:07 AM
Im not a box building expert, but im going to go out on a limb and suggest that this would be a bad idea. Most of the time, you want to stay close to the recommend specs for the subs, (but not always).

Sounds like thats not goin to be enought port area, but like I said, im no expert

01-16-2008, 11:08 AM
you talking about a common chamber?

01-16-2008, 01:39 PM
there is nothing wrong about having the subs share a port, or share a common chamber (for ported boxes). if your box is 14' tall, and 12.5 tall internally, and you went with a 3" wide port, this would give you 37.5sq" of port (12.5 x 3 = 37.5). for a 3cu' box thats not that bad. i don't think you will have too much to worry about.

01-16-2008, 02:39 PM
Use aero ports to save volume.

01-16-2008, 02:41 PM
What size and how many aero ports do you suggest?

01-16-2008, 02:45 PM
2 4" flared ports would probably work.

01-16-2008, 05:54 PM
I common chamber dual subs in sealed as well. It is a mono system so why not?

01-17-2008, 01:22 PM
I common chamber dual subs in sealed as well. It is a mono system so why not?

if one sub blows, you just doubled your air space for the remaining sub and, depending on the enclosure size and sub parameters, you could also blow the other one.

01-17-2008, 01:50 PM
In a sealed box, academically speaking, the subs won't be of equal power. In a common chamber sealed box, the stronger sub, which can compress air faster/better, could wear out the weaker sub as a result. Even if one is only slightly weaker, this could be an issue; and we aren't talking about aerospace grade stuff here where subs are within .0001 tolerance for specs. I would keep subs seperate in a sealed box. In a vented box, compressing air is not as much of an issue. However, since this is academic, it could take a century for any of this to happen, so take it for what it is worth.

This is similar to just replacing one piston, rings, valves, etc. in an engine with 150K on it where the stong link wears out the weaker ones prematurely since it is that much stronger.