View Full Version : Fi BL box built wrong

07-11-2008, 10:24 PM
Hey, my friend has an Fi BL 12" with pf option running at 1000w RMS by a Kenwood amp, and I think the box was built wrong... the total height of the box is 14 inches and the port is only 5 inches tall with a port width of 2.5 and a wall of 11.9 inches, so there is a wall and a wall on top and the other wall is the wall of the box and the bottom of the box, those make up the four sides of the port, it's a goofy looking port, small..

But it's supposedly tuned to 32 hz, the dimensions (outer) are 24Wx14Hx13D and it's not as loud as it should be at all.. was this box built wrong?

It's in an '06 Mustang? That's about 2 cuft internally I think after port (which is probably wrongly done) and sub displacements.. would rebuilding the box with same dimensions with a port as tall as the box and 3-4inches wide and tuned correctly (more sq in of port) increase output of the sub even though it would lower internal cuft a good bit? What if we were able to rebuild it with bigger port like that but with bigger dimensions all around so as to keep the overall 2 cuft internally, would there be significant output increase over the box he has now?

Thanks, sorry for the big read!


07-11-2008, 11:54 PM
I would make the port a good amount larger...thats very small. But 2 cubic feet shouldnt be a problem..but you could always drop it a bit...My friends SSD 12's are in 2.3 cubes a piece and do just fine.

But yea, I would rebuild and go with more like a 40 sq inch port or so tuned to around 32Hz

07-12-2008, 03:41 PM
if that is 2 cubes that port is 1.5 inches too short. also with 2 cubes you need much more port area than 12.5 sq inches! I would shoot for in the very least 30 sq inches of port ideally I would go for 40 sq inches

07-13-2008, 11:31 AM
I definitely think going with more port area would increase output a bit, even if it sacrifices a bit of volume.