Need help with rear port air velocity.
 

I am building my first box for a Fi Audio SSD12. I am powering it with a JL audio 600/1V3 and have decided to go with a slot ported box. I've never built a box before and all i know about it is what i can find from different web sites, forums and you tube. I've designed a box in WinISD that is 2.0 cubic feet tuned to around 34 Hz and the rear port air velocity is off the chart. Most of what I've researched says to have a cross sectional area between 12-16 cubic inches per square foot. The lowest i can get the air velocity is around 66 feet per second and that's with my cross sectional area slightly over the recommended 32 square inches. I am wondering if I am using the program wrong or if my design is simply going to be just outside the "standard". If i go step outside what I have found as recommended, what paramaters are safest to stretch. My end goal is a nice balance between sound quality and spl. Thanks for any advice.

I have the same sub for my daily setup and SSD's require alot of airspace to get loud. I would try to design a box for more airspace like 2.5cu ft. net and keep it at 14 in3 per foot. The SSD is peaky and putting it in something like 16inches per foot would enhance that and don't worry about vent mach unless you are trying to achieve high spl

Thanks for the advice. I'll definitely take your advice if i can work the extra .5 into the trunk and i'll rerun the numbers at 14in3

If space is of concern a flared aeroport is your best bet, plus its easier to design. Creative Sound - Product Details