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View Full Version : Can someone help me with Aero port lengths?

528hz
11-29-2008, 12:31 PM
OK...my box dimensions are as follow:

13 H x 31 W x 25 D = 4.6 cu.

Now...I also need to find out which would work best, 4" or 6" aeros.

I need it tuned to 32 hz, and 60^2 in. of port area....

11-29-2008, 12:37 PM
two 6" aeros = 56sq in I believe

four 4" aeros = like 50-51 sq in iirc

grimreper912003
11-29-2008, 12:41 PM
Straight Length Port required 27.96
Flare Length Port required 28.96

With 2 6" aeros.

www.psp-inc.com

528hz
11-29-2008, 12:52 PM
Straight Length Port required 27.96
Flare Length Port required 28.96

With 2 6" aeros.

www.psp-inc.com

Yeah, I used psp's calculator, I just didn't know how accurate it was.

Wanted some confirmation.

DBfan187
11-29-2008, 12:57 PM
Very accurate.

Xprime4
12-12-2008, 12:40 PM
is there a point to adding more than one areo? I'll be building a box this week-end 8ft/cu for a 18q. I want to tune it at 30 or 32 with a ****** 6 inch areo port. They say :Straight Length Port required 4.91

is that accurate?

Xprime4
12-12-2008, 12:42 PM
or should i do 2 x 3 inch x 2.46 ? any difference?

bball09124
12-12-2008, 12:49 PM
or should i do 2 x 3 inch x 2.46 ? any difference?

A huge difference. For each cubic foot of box you need 12-16 sq in of port. For an 8 cube box, I'd use no less than 3 6" aeros.

A 2 x 3 inch port would act like a hole in the box rather than an actual port.

Xprime4
12-12-2008, 06:25 PM
A huge difference. For each cubic foot of box you need 12-16 sq in of port. For an 8 cube box, I'd use no less than 3 6" aeros.

A 2 x 3 inch port would act like a hole in the box rather than an actual port.

so http://psp-inc.com/ isn't accurate at all. Coz they did asked my what was my box size and all.
Volume of Box in Cubic Feet: 8
Tuning frequency 32
Port diameter 6
Number of Ports 1
Straight Length Port required 4.91
Flare Length Port required 5.91
???:confused: so confused

Does the port got to be a minimum lenght? Why does PSP give me short port like this ?4.91 seems short as hell to me but the store around don't sell anything longer than 5 inch ( in 4, 5 and 6 diameter size)

Xprime4
12-12-2008, 08:15 PM
Psp calculator got me lost. Anyway for my to get a 32hz tuning with any number of port that are max 5 inch in lenght? In that case port area is diameter x lenght? how many square inch I need for my 8ft cu box? 12-16 sq inch per ft/cu is alot imprecice to me. What tuning it's gonna give?

bball09124
12-12-2008, 09:42 PM
Psp calculator got me lost. Anyway for my to get a 32hz tuning with any number of port that are max 5 inch in lenght? In that case port area is diameter x lenght? how many square inch I need for my 8ft cu box? 12-16 sq inch per ft/cu is alot imprecice to me. What tuning it's gonna give?

The concept isn't that hard to grasp. The surface area of a slot port with the dimensions 6x10" is 60 sq in of port. How deep the 6x10" port is determines the tuning. If the port is short, the tuning is going to be very high. If the port is long, the tuning is going to be very low.

Now you take an aero port. The surface area of a 6 in PVC pipe is 28.26 sq in because (pi x radius squared) is (3.14 x 3 squared) which is 28.26. So if you were to use three 6 in aero's that would give you a port area of ~84 sq in, which is close enough to the standard of 12-16 sq in per cubic foot of box. Now, plug your specs in to the PSP calculator. Each flared port would have to be 24" long.

If you were to use only one 6" aero, to acheive a tuning of 32 hz the port would have to be ~5 in. With the flare's, the smallest length you can get is 6" I believe. A 6" port only 5" long would act as a big hole moreso than it would a port in your situation.

If 24" for three 6" aero's is too long, you could run two 6" ports 15" long to acheive 32 hz tuning in a 8 cube box.

Let me know if I was not clear on some point, or you want me to explain something further.

Xprime4
12-12-2008, 10:36 PM
The concept isn't that hard to grasp. The surface area of a slot port with the dimensions 6x10" is 60 sq in of port. How deep the 6x10" port is determines the tuning. If the port is short, the tuning is going to be very high. If the port is long, the tuning is going to be very low.

Now you take an aero port. The surface area of a 6 in PVC pipe is 28.26 sq in because (pi x radius squared) is (3.14 x 3 squared) which is 28.26. So if you were to use three 6 in aero's that would give you a port area of ~84 sq in, which is close enough to the standard of 12-16 sq in per cubic foot of box. Now, plug your specs in to the PSP calculator. Each flared port would have to be 24" long.

If you were to use only one 6" aero, to acheive a tuning of 32 hz the port would have to be ~5 in. With the flare's, the smallest length you can get is 6" I believe. A 6" port only 5" long would act as a big hole moreso than it would a port in your situation.

If 24" for three 6" aero's is too long, you could run two 6" ports 15" long to acheive 32 hz tuning in a 8 cube box.

Let me know if I was not clear on some point, or you want me to explain something further.

:confused: I feel stupid. Wow 3 aeroport of 6" x15 = a big loss in net volume :p:
What if i can only have acces to non flared aeroport? like straigh one. Like I said, at the local shop they only sell 5 inch deep port with a diameter of 4, 5 or 6 inch.
What's possible for me? will i need like 10 aeros? Can i buy pvc tube from homedepot or something like that?

I just don't understand why using less port with less lenght still give the same tuning, but at the same time i can't go under 12 sq/feet... It look some much more complicated than Re L ported calculator

jdawg
12-12-2008, 10:49 PM
lowes and home depot and **** have 6, it might be an isle over, its actually drain pipe and it might be green

Jeremy M
12-12-2008, 11:30 PM
i seen some pipe at HD, 6" x 24".....cost was like 30 bux.

i almost bought it.

roarzorz
12-12-2008, 11:37 PM
The 12-16 rule is for slot ports. Round ports do not need as much port area.

budget76
12-13-2008, 12:10 AM
i seen some pipe at HD, 6" x 24".....cost was like 30 bux.

i almost bought it.

\$30:eek: **** the price jumps, I just paid \$6 for a 2foot section of 4" PVC.

Cabin_Pressure
12-13-2008, 10:07 AM
http://www.carstereo.com/help/Articles.cfm?id=31

Xprime4
12-13-2008, 04:12 PM
http://www.carstereo.com/help/Articles.cfm?id=31

Ok from what i understand, there is many way of getting the same tuning with different port and lenght. But you still have to have a minimum port sq. so if my box is 8ft/cu with an Fi Q 18 with 27mm of xmax and a tuning of 32hz, i'll need 12,99 minimum diameter and minimum 132,53 inch/cu of aeroport.

Then, if i put everything in the good case with 6 inch aeros, i'll need them to be 14,21 lenght. so. so Pi x Radius 2 for the port area = (3,14 x 9 x 14,21 ) x 2 = 803,15 inch /cu of port??? :confused:

Xprime4
12-14-2008, 12:40 PM
ok just came back from homedepot. They got 3 inch x 6 feet and 4 inch x 6 feet (i think it's external dimension)

the box is gonna be those dimension : 37.25 width x 21 height x 22 deep for a total of 8.3 before all displacement. The port are gonna be on the from left to right / right to left of the box and sub facing top ( no other possibility , that's the only way i got 6 inch clearance in front of port). Is it possible to do something with the 4 inch port? pm me a working design and you'll get a small paypal donation :D
I'll be using 3/4 mdf, 32hz is the wanted tuning ( minus possible) on a fi Q 18.

thank you i'll be waiting for pms from good designer. And no i can't find anything bigger :( The aeros will just be lenghty ( 37,25 - 1.5 mdf - clearance) will be the max lenght

Xprime4
12-14-2008, 01:02 PM
4 aeros of 4 inch x 13.01 (straight one) = (3.14 x 16 x 13.01 ) x 4 ports = 2614 inch/cu.... does that work?

Xprime4
12-14-2008, 05:16 PM
lil bump for a lost guy :(
4 aeros of 4 inch with a lenght of 13 inch each for 32hz tuning in 8.3 ft/cu ??? :confused:

Xprime4
12-15-2008, 12:02 PM
lil bump :( if i ain't getting anwered i'll need to do a another thread, which is annoying to everyone :(

rain377
01-03-2009, 06:40 PM
so whats and easy way to figure out how much port are u need when using areports? Im building a box thats 4 cuft for 1-15" i was thinking about going with 2 6" aeroports but thats seems like a lot now.

jdawg
01-03-2009, 06:47 PM
so whats and easy way to figure out how much port are u need when using areports? Im building a box thats 4 cuft for 1-15" i was thinking about going with 2 6" aeroports but thats seems like a lot now.

it is

rain377
01-03-2009, 06:48 PM
so then what would be the recommended?

jdawg
01-03-2009, 06:49 PM
i dont know what sub, or power, or box size

rain377
01-03-2009, 06:51 PM
1-15" bl fully loaded in 4 cuft and anywhere from 1500-3k watts

rain377
01-03-2009, 06:51 PM
ive never used aeros before so im not sure how to calculate it

rain377
01-03-2009, 06:52 PM
probably around 36-38 hz tuning

enoot
06-30-2009, 12:05 AM
3k on a bl? but id just do 2 4" and theyd need to be 10 inches long without flares

spl_robb
06-30-2009, 07:32 AM
lil bump for a lost guy :(
4 aeros of 4 inch with a lenght of 13 inch each for 32hz tuning in 8.3 ft/cu ??? :confused:

if you have 8.3 cuft before port and sub dis.

8.3cuft -.67cuft=7.67cft total.

ok this is what you need.

4"port x 15 long

westman995
06-30-2009, 06:22 PM