small enclosure/low tuning freq/vent length?!

[dexjam]

I'm interested in the SD2 D4's for a shallow mount build. I would like to know how you would find the vent length for the very small enclosure recommended by the Sundown website. When I calculate vent length, I'm getting really long vents in order to tune to frequencies even as high as 45hz. Even with small port area, I'm still getting vents that are much longer than what is practical. The website suggests using a 0.5 cubic foot enclosure if you are venting, and 0.25 cubic feet for sealed. The website does not; however, specify a tuning frequency or vent size or length. Any help would be greatly appreciated.

[Bradprobert]

you will have to increase your box volume to end up with the net volume of 0.5

that will be after all displacements. the port is a displacement and if youre using torres, it will calculate it for you. even though its a shallow mount it will take up quite a bit of space in a ported box. for that sub and what it seems like you are trying to acheive in size, just do a sealed box.

[dexjam]

Thanks bradprobert. That was the conclusion that I came to also. I think I will do sealed.

[the moose]

You could also try a sub box w/a wider face and mount your port tube on the outside of the enclosure using 3" plumbing pvc pipe with an elbow, thus retaining your internal box volume. Tuned ports work the same way, whether inside or outside of your enclosure

Edited May 4, 2013 by the moose