Port

[loganberry]

new box is gonna be around 7 cubes before displacement, idk how to find out displacement but 2 lvl 4 15"s will be goin in and the pipe is 4 inches around, how many will i need and whats the length on each...i want a 32-34hz tune please!! thanks alot for the help SMD

[loganberry]

precision port calculator said 6.64 inches for a 6.5 cube box and 33hz tune, thats for 2 4" pipes, that sound right? sounds a lil short to me

[E a r t h]

I didn't find any displacements listed on the DC site, but it should be around .2 cubes for each 15'' sub so you're looking at .4 for both. Range is prolly like .17-.21 for displacement on 15s more than likely. Are you using aeroports? Because I think 4'' aeros are like 12 square inches due to the flared ends, i could be wrong on that though. If you use pvc its going to be different then that anyway. With that in mind you're prolly aware of the 12-16 of port per cube general rule I'm shure. Depending on your net volume reached after all displacements, you can do the math.

Are you dead set on 4'' ports?

[loganberry]

I didn't find any displacements listed on the DC site, but it should be around .2 cubes for each 15'' sub so you're looking at .4 for both. Range is prolly like .17-.21 for displacement on 15s more than likely. Are you using aeroports? Because I think 4'' aeros are like 12 square inches due to the flared ends, i could be wrong on that though. If you use pvc its going to be different then that anyway. With that in mind you're prolly aware of the 12-16 of port per cube general rule I'm shure. Depending on your net volume reached after all displacements, you can do the math.

Are you dead set on 4'' ports?

yes im dead set on the ports cause i already have the 4" pvc pipe, ive used that site before and its been accurate, that just dosnt sound right to me 2 6.6 inch long by 4" ports for a 6.5 cube (roughly) box

[Boon]

You'll want 4 ports at the very least.

In high powered builds I use 2 4" ports per 12" woofer.

So in your case I would be using 8 of them, or 2-3-4 6" aeroports.

[loganberry]

ok so ill use more then 2, dosnt matter how many i use i just need help finding the length of them..can anyone help me there =\

[loganberry]

any help? i can always do a l port but i dont want to, i wanna use these!!

[99vic]

who needs ports? go sealed

[ALPINE408]

Do 4 12 to 18 inches long to start then çut till you get the sound you want

But use 4 not 2

[Nightshade]

precision port calculator said 6.64 inches for a 6.5 cube box and 33hz tune, thats for 2 4" pipes, that sound right? sounds a lil short to me

That's exactly what I got, but I'd reccomend going with more port area for 15's. Try a 6 inch aero per sub. That's 27sqin of port per woofer and will be better than just 12.5sqin which is what a 4" aero is. Imo I'd do 3 4" aeros per sub to get almost 37sqin of port per 15. Because that would give you a total of 11sqin of port per cubic foot and would work out great. Only problem is that the port would have to be pretty long. Here are both ideas that I would try before a single 4" per 15.

First idea single 6" aero per 15, so 2 total: 6.5cuft internal volume tuned to 33hz would need the port to be 17.14" long which is about the stock length they come in so no cutting would be required.

Second idea with 3 4" aeros per 15, 6 total ports: 6.5cuft internal volume tuned to 33hz each port would have to be 25.78" long so it's not that practical.

I'd would honestly try 2 6's over 2 4's. You won't have to cut the ports down and you'll be happier to add more port area because it'll make your box a whole lot louder. You don't have to listen to me, but I do know what I'm talking about when it comes to aero ports :hairtrick: :hairtrick: :hairtrick: :hairtrick: :hairtrick: :hairtrick: :hairtrick: with 2 12's off of 1900 watts rms.