One of the head guys for a "big" local shop down the road came in today. He had 4 12's in his own truck and said their shop was getting ready for the SPL comp I am hosting on the 19th.
He said it was pretty loud, but his installers didn't know how to get it louder....
I walked out and looked at the ~03' ext cab chevy. 4 350w Crossfires on 2 crossfire 600d's. Each sub in its own chamber, 2 seperate boxes, everything firing up.
Each chamber had a 3.75"x3.75" port, he said his installer said it was tuned to ~45hz. I estimated it to be ~35hz (on paper)...told him most of those chevy's peak at 45-50hz though.
The install looked ok on the surface, but I didn't dig very far into it. The amp rack was nice, I'll give em that...but the 2 600d's weren't even strapped. When I told him he should strap them so you can control both w/ one amp and the subs will all get the same signal. He looked at me like I was speaking a different language. He actually told me, "this thing is grounded like crazy". ...um...ok....sure.
Looked like the over all install was done pretty well, but the box was just WRONG. Prolly doing 141-143dB w/ the 4 12's.
He asked me for a box design, I was nice enough to gave him dimensions for my 2-15 design I've done in customers vehicles that wanted loudish daily bass. 8cuft, ~38-40hz on paper, subs up, port to drivers side, w/ doubled baffle and threaded rod braces. Guess I just felt bad that a his "pro installers" couldn't even come up w/ that design or something better than they had.
I wonder what they show up w/ at the show
Also, he said my 3 DD3515's on 1 ia20.1 @ 1ohm hurt his ears.
He actually told me, "this thing is grounded like crazy". 
