Box design for 98 Neon

[jayrulz223]

Hey, starting to build my first box for a buddy of mine, but i have a few questions about how exactly to port.

The dimensions i have to work with are :

Depth = 26in

Width = 32in

Height = 18

I'm trying to have it tuned to about 35ish.

Subwoofer is a 15'' Type R, with the old style surround. can't find the specifications for box sizes, but i figured SMD would be a better resource.

I attempted to use the RE speaker box design but i don't know exactly how i should port it, or how to decide the port length and the port width. I've seen alot of the crazy thing's on this site, and you've been the inspiration for me finally building my own boxes. Thanks for any and all help

[andym85]

they recommend like 2.25 cubes....here is what i did...its 2.28 cubes net, 35.22hz, mount the sub beside the port

the 16.5" on the side is the internal height (height of port), total height of box is 18"

[jayrulz223]

they recommend like 2.25 cubes....here is what i did...its 2.28 cubes net, 35.22hz, mount the sub beside the port

the 16.5" on the side is the internal height (height of port), total height of box is 18"

Thanks alot man, but just for understanding purposes, how did you figure how wide/long to make the port? I'd like to understand this so i could drop a few formula's and figure the correct port designs. The box look's nasty, i'll be sure to post a build log or something here, thanks again

[andym85]

i use an excel calculator that i made...looks complicated but its not...just a matter of tweaking dimensions and port length and area to get the desired volume and frequency...excel makes it easy

port length is measure down the middle of port

Av = vent area

Lv = effective length of vent (effective length = physical length + end correction <---1/2 of the ports width)

Vb= net volume in cubic inches

Fb = tuning frequency

Fb = .159*((Av(1.84*10^8)/(Vb(Lv+.823*Av^.5))^.5

[andym85]

oh...u wanna keep port area to like 12-16" of area per cubic foot....and length determines tuning

[98GCLimited]

"Lv = effective length of vent (effective length = physical length + end correction <---1/2 of the ports width)"

I was wondering about the end correction. Is that added for both ends of port or just one?

[andym85]

just one....only for a slot port also, so since that port is 2" wide, the end correction makes it an inch longer than it physically is (due to using the wall of the box as a port wall).