Hi There
I have been researching on how to design a slot ported box. I'm having trouble figuring out exactly what size I should build the port. I'm putting a single dc level 3 12 in a 1.25 cu ft net box tuned at 35 hz per dc. Due to the size of the cabinet I'm placing the sub in my boat the depth of the box can only be 9 inches. I planned on building the box 21x20x9. The sub will be on a 21x20 side. I'm having trouble figuring out what width the port should be and also a length that has a port ratio near 6:1 as well. And does it matter that the port will most likely need a 90 degree bend and the bend will be parallel to the rear will be longer than the piece parallel to the end that leads to the face of the box. I attempted to play with win isd and also found some calulations on the web. It showed to multiply 1.25 (net volume) x 16 to figure port area. So my port area should be 20 square inches. Take the calculated port area and divide by the height to get the width. Is the height of the port normally the height of the box? I just don't want any port noise. I will be powering the sub with 900 watts rms and I play my music at high levels in order to hear the music while I'm outside of the boat.
Thank you for any help, it's much appreciated!
