So I figured I would start a thread on this for the few who asked about progress. I have been into car audio for years. Mildly competed. Few shows here and there. Got a good deal on this 1998 Chevy Astro van and figured I would do another build the way ive always wanted to do. Now one thing, This is not a daily driver. This is a audio competition specific vehicle. That being said there is around 1000lbs of concrete in the back. This build will have a 4th order bandpass enclosure housing 4 x 15 inch subwoofers in small sealed tube boxes within the outer shell. I will be running lithium batteries as my battery bank for the substage and running around 40'000 watts of power to the subs at minimum.
 
With that being said onto some pics. I first got the van I stripped the entire interior just about. Only thing left are the front door panels (which are going) and the dash (which is staying). I started by laying the frame work out for the concrete. I used fiber reinforced concrete to prevent cracking. Pretty strong stuff. It does not need to be perfect as I will be laying fiberglass over top of the concrete to seal it and reinforce it.
 

 

 
After The concrete was all poured out I started on the frame work of the box. The rough framing is all 2x4's. There will be around 120 of them making the shell. 2 layers all around cross layed and screwed every 3 inches.
 

 

 

 
 

 

 

 

 
Now I started on the loading wall. At first I had the port at the center of the enclosure which I chose to change to drivers side port. This will yield better output. Now at this point most of this shell is framed out. Few minor spots to fill in and the shell will be finished and ready for plywood. Inside of this shell will be 2 layers of 3/4 birch plywood glued between the sheets and screwed every 3 inches throughout.
 

 

 
 
 
So at this point this is where I am at now. I will update when I get some more progress. Waiting for the subwoofer tubes to be made. Will update this when I get them in.

There are people that are into car audio and then there are people that are INTO car audio. Dear lord!!!! That is pretty insane.

Violence...I... *walks away* 
 
 
Keep this updated man :D

Nice! 10K per sub is pretty crazy. Do you have the equipment yet? I wanna see the subs, alternators, amplifiers and batteries your gonna throw down.

As of this moment i will be running B2 audio lithium batteries, 4 x 15" Ampere audio 4.0 subwoofers and 4 Ampere audio 9.0 TFHE amplifiers. That is the game plan at this moment. Will run a pair of amps strapped per pair of subs. Should net me 40k watts at 14.4v or so easily. Alternators will come from Singer alternators. Mike is a good guy. I have dealt with him in the past

That's nuts! Keep us updated.

Will the glass stay in this thing at full tilt?? Does the concrete offer better sound production. I know nothing. Quite a project man.

Violence.
As of this moment i will be running B2 audio lithium batteries, 4 x 15" Ampere audio 4.0 subwoofers and 4 Ampere audio 9.0 TFHE amplifiers. That is the game plan at this moment. Will run a pair of amps strapped per pair of subs. Should net me 40k watts at 14.4v or so easily. Alternators will come from Singer alternators. Mike is a good guy. I have dealt with him in the past

Nice, that's some serious power. I've heard good things about Ampere audio stuff. A guy on the SMD forums runs 6 of the ampere 3800's on 6 crossfire 18's.

Well it is Cool Looking so far and I will not have to worry about my Trunk being Bounced of the road at a Stop Light.
I cannot want to see how them Speakers are going to Mount.

Its nice to see how much difference there is between builds in there and here. Willing to see how this build ends up, keep it up!