port question

[brent338 0]

newb box help

So I think I might be able to fit two 18" BL's @ the min. cubes of 5 per sub.

just curious if I'm calculating the port disp. right...

12-16" per foot, so I shot down the middle with 14", which gives me about 1/2 a cube per port, but somehow this doesn't seem big enough...

so how many cubes per sub for port?

thanks...

[Acidburn 10]

so 10 cubes total?

that'd mean 140 sq inches of port

what tuning frequency?

[brent338 0]

I'd say 31hz would be about ideal for 18's... no/yes?

[Acidburn 10]

I'd say 31hz would be about ideal for 18's... no/yes?

That'd work.

That gives port length of 29.5 inches.

Ignoring the displacement of the wood (will vary depending on how the port is situated), the port will take up 2.39 cubic feet

[Acidburn 10]

This gives you some idea how huge this box would need to be

[brent338 0]

ok cool, didn't know they had a free box calc. out there...

I played with the #'s a little, 44w X 25"d X 25" high, as thats about as big as I wan to go, and got 9.5 cubes, after sub disp. that leaves 9 cubes...need 10 min to do the 18". so I take a few more carefull measurements and see if I can squeeze another cube in there. if not then 15's i guess...

thanks man!