I bought this sub a couple of weeks ago, built a box for it (1.4cuft 38hz), put it in and it sounds like shiit. It's a used sub, so theres no telling what it went through before it got to me. I can not give it any power at all because it slaps around and sounds like garbage. I've tried 2 different amps on it, same result. It sounds pretty **** good at low levels but you turn it anywhere past 50% power, it starts that sound at the top of the excursion. Does this thing need to be reconed? I'm about to say **** it and throw it in the trash. This is the same situation as that ******* last week blaming the box he bought, except the problem was his sub. I think this is the same deal. Thoughts?