It sounds good the way it is, there is some resonance, but that was something that couldn't be worked around. Usually, its from an annoying bass note though that sounds bad like that no matter what the enclosure type is.

I have never had a problem with the woofer over excurting in this box from unloading the sub, the design all but eliminates any chance of it.

 

When I had my subwoofer facing up towards the roof of my truck, I kept getting the over excurting/popping noise, so I went back to it facing forward.