Sundown Audio SA 8 first vented box build help!

[tony_collett16]

Hi all,

I would very much appreciate some advice. I have a bmw e36 convertible and I have built a wedged subwoofer box through the ski hatch. I currently use a B2 Audio 8 inch subwoofer from Sweden and its great. Althogh I would like some more SPL and I love the look and sound of the SA 8, although I have never built a vented box.

The measurements are as follows (using the RF box wizard online:

Height 9 inches

Width 9 Inches

D1 - 21.5 inches

D2 - 18.5 inches

Internal VB - 0.6 cubic feet.

So its a long rectangle box, with the current subwoofer and possible SA8 mounted at the front and the vent would have to be at the rear of the box.

Could some people give me some ideas of how to be make a vented box using the above measurments and tuned to a good frequency for a SA8? I know its a lot to ask, and many thanks in advance.

Tony

[01B4000]

http://www.stevemeadedesigns.com/board/topic/38791-torres-box-tuning-calculator-updated-818/page-29?hl=%2Bbox+%2Bcalculator#entry2517899

Use this calculator and I'd tune the box to about 35hz for SA-8. You also need to make sure you have 12-16 quare inches of port area per cubic foot for it to vent properly.

Good luck

[ToNasty]

Best size I've found for sa8 is .75 after displacement with 14" of port per cube

[tony_collett16]

Thanks for the advice. I must say I have never built a vented box before, so it will be cut, glue and hope for the best. Can you tell me what type of port would best suit the box I have. It would like something like this

I have found this off one of the forums. So basically my sub would be facing out to the left from the box and the port would be at the other end. Would a port like this be suitable. Also if someone good with maths can teach me how to measure the port size and length as I have never done this before. The box is basically 9X9X20.

Thanks again for the replys.

[tony_collett16]

I found a few port calculators online and this is what I can come up with using my box size. The freq set at 35 and volume of .6, I will use a slot port 1 inch wide by 7.5 high (similar to the picture). I have been given 2 lengths of 24.7 and 25.2, does this sound about right?