port length for 18" ssds

[cappucino 0]

need help with port length for a box for 2 18" ssds. current box is 48 x 24 x 24 external, 46.5 x 3" slot port tuned to 32Hz. I want to build a bigger box with a bigger port. What would be the port length for 48 x 24 x 31 external with a 46.5 x 4" port tuned to 31Hz.

[Fi Car Audio 64]

Port would be 13" long to tune it to 31Hz.

Not a huge change in overall repsonse. It will move your peak from 49 to 43 Hz and move the f3 from 30 to 27Hz. Gains you a little on the bottom end. Not sure if it is really worth the work to redo it for an incremental gain.

Are you wanting it to drop lower and deeper, more SPL, or?

Thanks,

Scott

[cappucino 0]

im looking for both, more spl, along with better low end extension, that's why i wanted to go with a bigger box and bigger port, the only thing that restricts the size of the box is the depth because if it is any longer than 31", the port has barely any clearance. also, would it make a difference whether i used a slot port along the bottom 46.5 x 4 or a vertical slot port in the middle of the box 22.5 x 8.5? we have to rebuild a box no matter what because the first box made is falling apart (not enough glue in some areas along with no bracing). thanks again scott