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keep_hope_alive
08-17-2012, 11:00 PM
I am building an SPL setup for a friend. I have the plan and physics will dictate all dimensions. I will share the build process, of course.

End goal will be four Massive N2's and pair of Fi 18's in a mid 90's Astro Van. Will form a wall with two separate enclosures at the C-pillars to retain 4 seats.

First is a single sub on a single amp.

The enclosure will be 3" of concrete. I know how I am going to build the forms with 3/4" OSB.

The first step will have the enclosure facing back, loading off a concrete "L".

The suspension will be reinforced. the enclosure will be rigidly secured to the vehicle. Roof and doors will also end up being reinforced.

Will be vented with a removable plug for SPL and run sealed for daily. Will use processing for the two modes.

Any comments/experience from you with concrete builds is welcome.

This will be fun.

kushy_dreams
08-17-2012, 11:02 PM
In for badassness :yumyum:

Joseph7195
08-17-2012, 11:09 PM
Tuned in for sure! You always give enough pics to explain everything properly and thoroughly, thus insuring I learn something. Plus I fap to a couple, sorry, nature of the game. :boink:

keep_hope_alive
08-17-2012, 11:11 PM
He has a good Clarion HU, Jl C5 comps, and the comps will be amped. Goal will be daily SQ. some local shops use a TermLab in the pass dash corner for local comps, but I'll refer to other rule books to determine classes ahead of time.

husker77
08-17-2012, 11:14 PM
What is he doing for suspension, it has to weigh a ton, literally.

keep_hope_alive
08-18-2012, 12:33 AM
Final weight is a concern, and the type of concrete mix will be chosen based on final design weight... But we live near Iowa, so if it can haul six Iowans around, it can haul some concrete...

CAT MAN
08-18-2012, 12:37 AM
i talked tto you on the phone about this. cant wait to see it :)_

goingdef
08-18-2012, 12:48 AM
Why are you going with a 3" thickness, with a good portland cement you should be able to pour a VERY dense rigid enclosure and not have to go beyond 1.5" in thickness also portland has a very tight structure to it after it has set-up, it's usaually mixed with sand to change it's consistency but I would use as little of that as possible.

keep_hope_alive
08-18-2012, 03:52 AM
I agree thickness can be varied based on cement used. Which affects other variables. Thinner with higher density can weigh the same... But something I will consider. That's the input I am looking for.

chillin
08-18-2012, 04:29 AM
Looking forward to seeing this

Kangaroux
08-18-2012, 04:29 AM
But will it blend?

keep_hope_alive
08-19-2012, 12:59 PM
But will it blend?

blend?

audiobaun
08-19-2012, 02:12 PM
I have seen on construction sites that Foam has been used,and (chicken wire?) wrapped around that, and concrete sprayed on top of that, and felt pretty solid when finished.I have also thought about the concrete board that is generally used in commercial buildings for rest rooms/counter tops for tiling ect.just a couple of other ideas possibly for concrete structure.Yet, I am Subscribed:santa:

Kangaroux
08-19-2012, 03:03 PM
blend?

Nevermind, lol

hispls
08-19-2012, 03:16 PM
I have seen on construction sites that Foam has been used,and (chicken wire?) wrapped around that, and concrete sprayed on top of that, and felt pretty solid when finished.I have also thought about the concrete board that is generally used in commercial buildings for rest rooms/counter tops for tiling ect.just a couple of other ideas possibly for concrete structure.Yet, I am Subscribed:santa:

Heard good things about cement board. Laminate together a few layers of that with resin on top of a few layers of wood laminated together with resin.

keep_hope_alive
09-22-2012, 10:30 PM
It's on.

ordered a Fi BL18 dual 2 ohm sub the other day. we considered the SP4 18 but the sensitivity is so poor, with our power we need an efficient sub. The Fi BTL N2 was our desire but the budget needs to be realistic (after the purchase i did see one for sale on here for $450 which we would have done). The BL18 should achieve the desired goals given the Massive N4 power.

will be concrete, thickness to be determined. i have 14 cu. ft. to work with (max external dimensions). with 3" thick walls all the way around (incl forms) that leaves 7 cu. ft. before port displacement.

i started a computer model of the vehicle in EASE. i will use it to model sound propagation and interference patterns at harmonics of the desired fundamental (100Hz low limit on calcs).

I'll design the layout in CAD ahead of time. goal is for a competed project in December.

keep_hope_alive
09-22-2012, 10:44 PM
the suspension has already been beefed up for hauling/towing so we don't have to worry about that right yet.

kushy_dreams
09-22-2012, 11:07 PM
I cant wait to see the finished results!

Spooney
09-22-2012, 11:11 PM
In for the build and results. Gonna be awesome.

keep_hope_alive
09-23-2012, 12:14 AM
I will start a build log in the right section when we start pulling interior.

Anyone got a preference in the concrete mis used? I assume fine and not coarse.

CAT MAN
09-23-2012, 12:14 AM
use coarse for a texture look. would be cool

snoopdan
09-23-2012, 12:43 AM
concrete setups are usually non-driveable after the fact. Just sayn'

stevew007
09-23-2012, 01:00 AM
the suspension has already been beefed up for hauling/towing so we don't have to worry about that right yet.

so what was done to the suspension? i had a 94 with the fiberglass mono leaf and it ****** for weight.the guy who bought it from me did bags and ended up busting the bag and rear leaf. I also hear that he had broke a control arm or a-arm off the frame and has been welded 3 times.now the van is too dangerous to drive.

also why concrete?why not steel structure lined with mdf or something? are you lining the concrete with anything like mdf? are you planning for just plain smooth concrete? how are you going to pour the concrete on the top of the box? the last extreme box i worked on had a back wall that was 10" thick the floor was 4"+ sides were 5".concrete is a lot of weight and dangerous as all hell to drive around with it.any upgraded brakes on the van?

I think someone is over thinking this build myself.but what ever i helped build one extreme vehicle and it was a total blast. but when it came to making change's like moving the back wall 5" hahaha i told him i was sick.

keep_hope_alive
09-23-2012, 05:13 AM
Thanks for the feedback. OSB will be used for the forms, a box within a box will be built. Making the face is the next challenge in my plan right now, the front may be a separate piece. I can put fasteners in the box pour.

Concrete is being used for mass, rigidity, and strength, as well as transmission loss. May only end up with 1.5" of concrete if we use 3/4" OSB. OSB is being used for obvious reasons (if you are familiar with concrete forms).

It appears the suspension upgrades includes upgraded leaf springs and frame work. It is a truck frame, which helps.

Through CAD I will be able to determine the cu. ft. of concrete in the design and thus the weight.

I am considering just making the back, inside, and front with concrete and let the top, bottom, and outside be reinforced wood to keep weight more centered and lower. We'll see.

Safety is a huge concern. A reinforced floor and roof will be required, welding is inevitable and not a hindrance. I have to determine forces and sheer strength of fasteners as well. I will be consulting with some of the structural engineers in my firm to verify my calcs. I will be approaching this with a very conservative mindset. No sacrifices will be made in relation to safety. I don't want to build something that will move in an accident.

mlstrass
09-23-2012, 05:58 AM
Concrete enclosure seems like extreme overkill for those subs off that power level.

Being a C pillar wall extreme SPL can't be the main purpose, so why not make it easier on yourself. Unless you're just wanting to have some fun with cement.

Either way GL with the build...

keep_hope_alive
09-23-2012, 11:19 AM
Concrete enclosure seems like extreme overkill for those subs off that power level.

Being a C pillar wall extreme SPL can't be the main purpose, so why not make it easier on yourself. Unless you're just wanting to have some fun with cement.

Either way GL with the build...

i don't think it's overkill for proper control of the rear wave to prevent cancellation through the enclosure walls.

mostly fun with concrete. something i've wanted to try, and i have a platform to try it on. materials are cheap. we may likely fab a standard enclosure while we build the big one.

Wanacustomx
09-23-2012, 10:49 PM
damnit it was my btl18 i needed to sell that thing man!!!!!

Kadori
09-26-2012, 11:43 AM
But we live near Iowa, so if it can haul six Iowans around, it can haul some concrete...

being an iowan, i lol'd

SourDeez
09-26-2012, 01:17 PM
Cement? Thats for sidewalks.