I'm getting an adire brahma 15" MK1 sub and putting it in a sealed box at 2.6 cu ft. Do you think I should put polyfill in this box? On winisd 2.7 cu ft brings it to qtc of .70X I'm gonna be powering it with a PG xenon 600.1 It's all ordered and on its way along with a set of PG RSD 6.5" components off a kicker kx150.2 I should have it installed by next weekend and will have pics up once its done.