Sub Enclosure Size!?

I've just found out the recommended sealed box capacity for my Kenwood sub and its 28 litres :banghead: does anyone know how i can make sense of this? is there some kind of measurements i can take of the box (i built) and convert it into litres? just so i know if the box has adequate space? :uhoh:

Also - the box i've built is for my two kenwood subs (the same kfcw300s) and the recomendation i guess is for one, so would this make the recommended box size double 28 litres?

Cheers in advance! :popcorn:

if you are into math ...... 1 liter = 60.5 in^3 and 1 ft^3 = 1728 in^3

so 28 liters x 60.5 = 1694 in^3 or almost 1 ft^3 ... then you have to add the displacement of the sub to the size of the box. So a 1 ft^3 sealed box should be good. For a ported box, you will have a lot more work.