Basically, I have a ported subbox that's 1.3 cu ft roughly after speaker displacement. it's tuned to 37 hz. I have a buddy with the same in a 2.2 cu ft box tuned at 34 and I do notice his sounds louder and better. I have the speaker basically set up with the factory recommendations to keep it from unloading. Has anyone else went with a bigger box for this sub? How did it turn out? I have an 08 trailblazer and he has an 06 Impala. We both have the same hifonics brutus 1200 on these subs so I know the amp isn't the difference. Thanks in advance for all the help.