round port sidewall clearance

[jonny101abc]

im doing a 12" sonotube port for my box. but there is only 13.5" height in the rear section of my box.

so it gives me 3/4" top and bottom of the tube for clearance.

how much sidewall clearance do i need, for it not to get any port noise

John

http://i100.photobucket.com/albums/m34/jonny101abc/IMG_4472.jpg
http://i100.photobucket.com/albums/m34/jonny101abc/IMG_4438.jpg
http://i100.photobucket.com/albums/m34/jonny101abc/IMG_4437.jpg
http://i100.photobucket.com/albums/m34/jonny101abc/IMG_4448.jpg

[spltuscon]

That's not much clearance...personally I would switch to a slot port or a smaller tube (maybe 10"). I wasn't very impressed with using sonotube when I tried it myself...and it needs flares to work well.

[ascitiesburn69]

How big is that box????? It doesn't seem to have nearly enough airspace to require a 12" sono, which is about 113sq in of port... Unless you have a 10+ cube Net box I wouldn't use that.

[jonny101abc]

the box is 10.70 net, its about 44" long front to back

how long does a square port have to be to attain 30-32hz tuning, if the port goes down the center and is 12 x 10