Cut Sheet for Port

[Ryman]

I have my box figured out port and all just I don't know the dimensions for the port i need to cut if you guys could help and explain to me cuz i know that the length of the port is supposed to be the length centered not physical

Box Dimensions

Height - 16

Width - 35

Depth - 19.5

Port Dimensions

H - 14

W - 3.5

L - 22

woofer dimensions - .21

common port walls - 3

mdf - 1"

sub upward

This is going to be for an FI BTL 15"

[Ryman]

anybody? I'm trying to cut and assemble this today so i can have majority of the box done by the weekend just not sure what size to cut the port lengths

[fecupe2001]

the port is gonna aim to the roof or the back???

[Ryman]

back

[fecupe2001]

Well, since your port Width is 3.5" , you should try to keep it at least that distance from the wall of the box, said that, if you need 22" for lenght then you have to make a L port, 15" long the first piece and then 7" to the right

Edited December 18, 2010 by fecupe2001

[Ryman]

well trhats what i thought but isthere a difference between actual port length and physical?

[fecupe2001]

i don´t understand your question hommie.

[fritosaregood]

you want the center distance of the port to equal your port length, so you have to average both side of an L port to get the actual distance.

with fecupe's dims you would have one side 22" and with a 3.5" wide port the other side would be 29", so your effective length is 25.5 inches

what you need is a 15" side and a 3.5" side. that will give one side an 18.5" length and the other side a 25.5" length, so your effective port length with this is 22"

[Torres]

say you have a box. port length is 10" long. that's the actual port length. one baffle at .75" makes the physical port length now 9.25". the baffle accounts for the missing .75" still making the actual port length 10". now say you have 4 baffles at .75" each (totaling 3"). now the physical port length is 7" while the added thicknesses of the baffles accounts for the missing 3" of the port. still accounting for the actual 10" of port.

so physical port length is the length the actual wood of the port needs to be. effective port length is the port length entered into the port length box.

[Ryman]

so why is the port calculator tellling me that the physical port length is 17.5 not 18.5 is that because it takes into account that one inch baffle?

and so fritos i understand what you're saying and i agree with you cuz it just makes sense so if the first leg is 14 inches then the next leg would be 4.5?