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cobra65427289
06-08-2003, 09:55 PM
i have a box that is about 4.1 cubic feet. i will be housing two 12" elemental k's. how long does 2 ports have to be for about 40 Hz?

cobra65427289
06-08-2003, 09:57 PM
forgot to add that the ports will be about 2" wide a piece.

ShaunMac
06-08-2003, 10:00 PM
Are the ports round?

cobra65427289
06-08-2003, 10:11 PM
yes, they are round
i got 6.64 inches for each but i dont know if i used winISD pro right.

ShaunMac
06-08-2003, 10:18 PM
You're gonna want more port area than 2 2" round ports for 2 12" subs.

You'll get port noise unless you add more port area.

cobra65427289
06-08-2003, 10:27 PM
what about an 8 inch by 3 inch rectangular port?

ShaunMac
06-08-2003, 10:32 PM
Originally posted by cobra65427289
what about an 8 inch by 3 inch rectangular port?
That would be much better. 24sq in. of port area.

Will you use one port or two?

cobra65427289
06-08-2003, 10:34 PM
at that size i would only have one port.

ShaunMac
06-08-2003, 10:38 PM
At 8" x 3" in a 4.1 cu ft. box tuned at 40Hz

A rectangular port(not a slot port) should be 5.8" long.

Are you mainly just looking for SPL out of the K's?

cobra65427289
06-08-2003, 10:46 PM
yeah, i figure the recomended for them is 25 hz and that is mainly for SQ so i figured i'd go a little bit higher.

ShaunMac
06-08-2003, 10:51 PM
Do you have a sub-sonic filter? You will want one if you are tuning that high.

cobra65427289
06-08-2003, 10:54 PM
actually i dont, i ordered the avionixx 800.2 and i believe it doesnt have one. what is the highest Hz. you recomend with out an SSF?