Concrete Sub Box

This van used concrete walls (just scroll down). I'm confused about this topic. The outside of the enclosure is covered in cement. Had it bonded with the enclosure, wouldn't it keep it from flexing?Jon

Don't like rockford subs? Then don't look at my car =)

I am assuming he use concrete tokeep the box from flexing which would be very fectve. I dont know any sub that is gonna make a 3/4 mdf box thats encased of an inch of concrete flex. When ever I have seen concrete used it was to stp flexing, and it is very effective at it. THe problem with it is the sever increase in weight that it adds to the vehicle.double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer

there is a group of home theater people who are using marble and concrete to make sub enclosures, the reson is it doesn't resonate (well at least not at any frequency that will color teh sound) that will make for a truer sound fiberglass and wood add some sound to the bass

Well the box was designed by a designer who works at powerbass. The concrete keeps flex down and cuts down on the resonance of the box. Weight isn't really an issue if you are a serious competitor. The tubes inside the sealed box are supposed to make the box act like it is ported and make it hit harder. NOT because the box is too big. Box for 3- 15"s is 8 cu ft. My ported box for the cab is 13.2 cu ft for 4 subs and it is almost 6 cu ft shy of what it really needs to be. Well anyway I constructed the box and did a test run with it. In conclusion after 3 hrs of trying to get it to hit harder than it did with my other set-up I came to the realization it sucked and is going to the trash pile. Gonna make a few mods to my other box and run it for this weekends comp. Thanks for all you input and links.

yeah, interesting topic. Sorry I sounded so pissy, I'd just never heard of concrete being used inside a sub box or for weather proofing resons. I have heard of people using it to stop flexing, I hadn't head of its anti-resonating effects, very interesting. I learned something new today "Shiny chrome when used in conjunction with bikini models is particularly effective in inducing brain deficit disorder"

02 Jeep Grand Cherokee

Monster System on its way.

No problem, it's all good, I put my old set-up in last night for Sunday's comp so I'm good to roll. I think I will tinker with the junk box and try to tune it with maybe shorter tubes. It sounded damn good till you threw alot of power on it and it started to clip extremely bad, sounded like all three subs were shot. I had it hooked up in the shop and think it may be mostly a voltage problem, amps draw a lot of juice. Power supply might not be as big as it was supposed to be. It'll be something to do this winter anyway.