I had a shop build my box for 2 dc lvl3 12s.. 42x10x20 up firing, I installed 2 alpine type rs while im waiting for the dc.
They didnt put any bracing inside the box but it is 3/4 MDF
After about 3 hours of play for the subs and box I started hearing a loud popping, slapping something sound on certin tones and songs. not all just some like "On my level" with wiz and too short.
I freaked out and took everything out and checked it. it all seems fine. i think one sub was a little loose, after trying it again the same happened but now it was worse.
I had a friend put all his weight on the center of the box between the subs and it got better with the more he pushed.
Is it leaking, loose? 50 pounds of sub made it come apart?
Or is it the new less then 4 hours of play time subs? Like I said, some songs with higher tones sound just fine