Help with aero's 1 6" and 1 4" or 3 4"

[Buck 5,000+ posts]

I think you should go 1 6" port. I had 2 4" on a 15 and 1 6" will be a little larger.

 

[Buck 5,000+ posts]

well like i said the internal volume is 5.6 before sub and ports as the calculators say so but im confused when it comes to figuring out how much area the ports are taking up. unless someone could tell me. i guess ill start with 3 4" ports at 12" to 14" and see how it sounds. hope all goes well

pi * radius^2 * length

 

[on1wheel01 10+ year member]

ok i think i will do 4 4" and just plug one up. if it sounds like crap ill just make a new plate. I've read the ports need to be 4" from any wall. but my sub mounting depth is like 8 7/8 and 14" ports that will be right on the magnet and if i slide the ports over they won't be firing into the cab through the ski port. maybe i should make them 12" long. hell i wonder if i should stay with sub and slot port back which would be louder?

 

[on1wheel01 10+ year member]

pi * radius^2 * length

not understanding that

 

[SPL Blazer 10+ year member]

You use the formula to find the volume of a cylinder, use the ports as a cylinder and there ya go.

This is how I figure out the displacement of the aero ports. I've seen and metered some decent enclosures with 15" subs, one with three 4" aero's, and one with our 4" aero's. They both had respectable numbers for the power used and I didn't see any noticeable difference between 3 or 4 ports. You will just have to take into account the size of the enclosure, the tuning freq you want and how much space you want to displace. I'd say go with three 4" aero's and tune them to the freq you want. Then figure out how long they will need to be to play the peak freq of your vehicle for doing an SPL comp. You should be able to swap out the ports as needed for doing a comp and then going back to playing music.

Just a rough estimate, figuring your enclosure would be 5 cu ft after displacements, running three 4" aeros tuned to 34Hz they would each have to be 15.65" long. When you run four 4" aeros tuned the same then each port would have to be 21.51" long. This is just an estimate, but you can see the difference if you go from 3 to 4 ports. Now if you were to go with a higher freq for comps, say 48Hz, then running three 4" ports they'd have to be 6.89" long. You can change the tuning freq by swapping out the ports pretty easy, once you figure out the proper displacements.

 

[on1wheel01 10+ year member]

Ok I was wondering about just swapping ports but if I did that how would I keep it sealed up? I figured I'd have to fiberglass the inside and silicone it all up. I figured like bunkerking said just keep one caped, but would I cut 3 of them at 12" and what to do with the 4th since at the high freq they need to be shorter, would I just cut the 4th at the 8" mark?

 

[SPL Blazer 10+ year member]

What I did was buy one set of pipes and cut them for daily, and another set of pipes cut to the correct length for burping at comps. You'd be better off running three ports for both daily and comps, that way your not worrying about losing pressure from your blocked off hole.

 

[on1wheel01 10+ year member]

Yea very ture what do you just take them out and re silicone them up after wards?

 

[on1wheel01 10+ year member]

ok screw it im just gonna go with 3 4" ports at 12" should be just fine that way lol i have a headache