The original idea for the mini was to have 3 13inch balls in the boot, but i cannot get them made so i had to find another way of fitting all the equipment in the minis boot. After trying a few ideas i settled on taking up the whole boot with a box for the 3 subs and mounting the amps front and back. The box has a seperate compartment for each sub and is made from 20mm MDF and sealed inside. It is really bassy, but needs setting up as i think it can give alot more.