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View Full Version : Help with aero's 1 6" and 1 4" or 3 4"



on1wheel01
03-07-2009, 05:52 AM
ok guys i have been reading a lot on here and am trying to understand all this. first off running a 15" dd 9515 running 2k to her rms. my max dimensions are 33 wide 16.5 high 22 deep. i think this is around 4 cubed my ? is should i run 2 6" ports or 3 4" or 1 6" and a 4". looking for 36 hrz or so. i would love to have the ability to tune at 36 and also 40 plus for spl using a plug so which would be best. since im cheap im prob gonna use pvc from lowes from what I've read they should be 12" long. one thing i don't comprehend is how to mount them to the box since they are not flared. box will be sub back port forward into the ski port middle of seat and box help please

iamamp3pimp
03-07-2009, 06:30 AM
i did it with storm tubing (it ***** up the resin better)

fiberglassed it from the back side, let that cure and then used a router/flush trim combo to cut the hole.

then rounded it over a little......this was using an 8 inch port diameter

on1wheel01
03-07-2009, 06:37 AM
sounds nice but i didn't really understand that lol. so ill have to fiberglass them??

iamamp3pimp
03-07-2009, 06:45 AM
do you have a plunge router?

on1wheel01
03-07-2009, 06:57 AM
not sure what that is so no lol, maybe i'd be better and just buy some? I've got 2 cheap ones that came in a band pass box they are 3" and 3 3/4" long. But dont see those helping since i need more. I had thought about making a few holes at the end of the pvc and the wall and using a very short screw driver mounting it that way then use silicone to seal it up(drill pilot hoes of coarse so it wont split would this way work>? And still wondering about the port sizes and # of them that eludes me the most. Ok using the re calc i typed my #'s in and making it a sealed box it's 5.5 cubes I know it wont be with ports but wow bigger than i thought maybe 4.5 after ports?

bunkerking09
03-07-2009, 07:06 AM
run 2 6" ports.

But I think they are going to have to be longer than 12", probably closer to 18-19".

on1wheel01
03-07-2009, 07:15 AM
don't think i can have them that long might touch magnet or be right at it i have the sub all to the Left but ski port is in middle of the box

bunkerking09
03-07-2009, 07:17 AM
don't think i can have them that long might touch magnet or be right at it i have the sub all to the Left but ski port is in middle of the box

Make the ports external :)

You will also have to take port and sub displacement into account, if you made the ports external, you gain airspace.

on1wheel01
03-07-2009, 03:34 PM
Ok i am using the http://psp-inc.com/ calculator and it is tell me if I have 4.5 cube(thats my displacement after everything I think)before ports and sub it is 5.5 i figure take away about 1 cube. So I typed in 4.5 cubes tuning at 36 and it sys 3 4" at 14.49" straight port. Now lets say I wanted to be able to get to 45 hz would I just put another port in at the same length?

on1wheel01
03-07-2009, 05:48 PM
Just gotta decide if I wanna do 3 or 4 4" ports, if 3 they will be 14" long. May try that and see how it sounds. I bought a 10' piece of think walled 4" pvc for $8 so will have plenty. Not gonna do external ports i don't think as the box will be right up against the ski hole as it is. I did get a cheap 4" pvc plug (well looks like a thin as hell plastic cap), but i wonder if it will make a gawdy noise if used.

on1wheel01
03-07-2009, 09:29 PM
bump

SPL Blazer
03-07-2009, 10:32 PM
Why are you guessing how much airspace you have? If your looking to add aero ports then do it right and figure out EXACTLY how much space you have, it's not hard. Go buy a tape measure and measure your box, then look at the subs specs in the owners manual and find your subs displacement, and use the various online calculators to figure out your internal volumes before and after your port displacement. And you say your adding aero ports but that you don't have flared ends? Aero Ports have flared ends, adding a round pvc pipe and using it as a port is not an aero port, it's just a round port.

http://www.the12volt.com/caraudio/boxcalcs.asp

on1wheel01
03-08-2009, 12:02 AM
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

roarzorz
03-08-2009, 12:16 AM
I'd do three 4" ports.

bunkerking09
03-08-2009, 12:20 AM
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

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

also, i would go with 4, then if you want to go with 3 you can just plug one

Buck
03-08-2009, 12:22 AM
I think you should go 1 6" port. I had 2 4" on a 15 and 1 6" will be a little larger.

Buck
03-08-2009, 12:23 AM
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
03-08-2009, 01:23 AM
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
03-08-2009, 01:24 AM
pi * radius^2 * length
not understanding that

SPL Blazer
03-08-2009, 11:30 AM
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
03-08-2009, 04:01 PM
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
03-08-2009, 04:11 PM
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
03-08-2009, 04:17 PM
Yea very ture what do you just take them out and re silicone them up after wards?

on1wheel01
03-08-2009, 05:19 PM
ok screw it im just gonna go with 3 4" ports at 12" should be just fine that way lol i have a headache