Sub box dimensions? what have you got and where?

[JAS0N]

I am considering putting a sub box into my 2.
I have had a search and tempted by the under dash box does anyone have this and if so would they be willing to share the dimensions, I am struggling to get any time to look at the car in daylight due to work and would like to build one to put in.
I have considered behind the seats and this is another option but would lose the little storage space there is there.

[martin_b]

Put one of these behind the passenger seat.

http://www.amazon.co.uk/gp/product/B008FYFBOI?psc=1&redirect=true&ref_=oh_aui_detailpage_o07_s00

Works fine with classic rock music, and as I've strapped it in, it can be removed in 30 secs if necessary.

[mikews]

I've made the passenger side storage bin into a sub enclosure, fibreglassed the inside and top so it's sturdy and mounted an old shallow mount sub I had knocking around. Padded the inside out with wadding and, although I've not been able to get it into the 2 yet, have tested it on a rig and it punches quite hard so will have to see how it sounds in the car. Cost me nothing and was just something to do.

[JAS0N]

Would rather a fibreglass build, the one I Built in the smart roadster had a jl in the footwell which punched a lot better  than an active sub.
I would prefer to look at a 6" jl sub under the dash or 10" alpine r (depending on space) in the rear storage bin.
This would not cost anything as it is audio gear I have doing nothing in the loft.