PDA

View Full Version : How to calculate displacement of round ports?



nVRuckus
11-10-2006, 11:48 PM
How do I calculate the displacemtn of round ports? Im gonna be running approx. 8-10 4" ports and will have to figure out displacement in my box when I decide on the tuning. What is the way to figure this out?

JimJ
11-10-2006, 11:53 PM
pi*port radius^2*port length

iamamp3pimp
11-10-2006, 11:57 PM
tell me the length.

nVRuckus
11-10-2006, 11:57 PM
pi*port radius^2*port length

so on a 4" port would that be 3.14*4*length?

nVRuckus
11-10-2006, 11:58 PM
tell me the length.

dont know yet. havent gotten that far, just want to learn for future reference as im sure this wont be my last round port build.

iamamp3pimp
11-10-2006, 11:58 PM
12.57 cubic inches, per port.

thats if you are going unflared.

if you are flaring them, it doesnt change much.

iamamp3pimp
11-10-2006, 11:59 PM
You talkin about Kennys build?

iamamp3pimp
11-10-2006, 11:59 PM
or the fiberglass one

nVRuckus
11-11-2006, 12:00 AM
12.57 cubic inches, per port.

thats if you are going unflared.

if you are flaring them, it doesnt change much.

not asking about area robin. Im doing total displacement.

4" port radius would be 2 so 2^2 is 4 right?

nVRuckus
11-11-2006, 12:01 AM
neither this is a new build totally seperate.

iamamp3pimp
11-11-2006, 12:01 AM
12.57 cubic inches, per inch in length per port.

thats if you are going unflared.

if you are flaring them, it doesnt change much.

i left that part out.

iamamp3pimp
11-11-2006, 12:02 AM
yeah i fuxxed that up when i posted it......long day.

is there a space/image limit on the gallery on TAD?

iamamp3pimp
11-11-2006, 12:02 AM
spam

iamamp3pimp
11-11-2006, 12:02 AM
4200 posts wewt

nVRuckus
11-11-2006, 12:06 AM
is there a space/image limit on the gallery on TAD?
not that i know of. I mean I put a limit on the total site but its like 20gb of monthly bandwidth and 500mb of space.

iamamp3pimp
11-11-2006, 12:26 AM
yeah im gonna uipload all my build pics over the next few hours hopefully, and they are only like 50k each, so it shouldnt be an issue

xluben
11-11-2006, 01:10 AM
How do I calculate the displacemtn of round ports? Im gonna be running approx. 8-10 4" ports and will have to figure out displacement in my box when I decide on the tuning. What is the way to figure this out?

8,000 posts and you don't know elementary school math :)

also, it should be mentioned that for true displacement it should be outer diameter.

so if the walls of the ports are 1/8" it should be:

Pi x ( O.D. / 2 )^2 x Length

not a big difference, but with 10 of them it could add up.

good luck with the build :)

JimJ
11-11-2006, 01:13 AM
I'm just imagining what 10 4" ports will look like...

A giant game of Whack-A-Mole.

Will you have something pop up at random? :D

iamamp3pimp
11-11-2006, 01:25 AM
lmao



yeah i'd personally use somehting a little more extravagant.


like a twelve'r.

only 113 squares @ a true 12 inches, but ****, that'd be ****, and much cheaper.

Goldtaz1
11-11-2006, 11:25 AM
Why not just use 6" aeroports vs. all those 4's. The 6's will provide better airflow and you won't need near as many ports. One 6" aeroport is equal to about 29 square inches in surface area, whereas a 4" is equal to about 13 square inches in surface area. Just a suggestion.

The 6" precision ports are available at www.thrilleraudio.com

rocky 59
11-11-2006, 11:34 AM
so if my box its 1.9xxx and i have a 4'' port. the port needs to be 13.3'' long to get 35 Hz?