Feedback on Crazy Box Designs

Do you think either will be loud? Both are roughly tuned to 60 Hz

Box 1




Box 2

im leaning towards the top one.

how would you support it????

as for the second..... angling it up is probably bad.... try starting at the bottom and have it horn out to a massive size....

i like number 2. you live in houston right? ide like to see one of those boxes when you get done if you're willing.

They would both work rather well.

@ DBDaddy,
Absolutely. I should have something interesting at the Hurricane Alley Drag. If it gives decent numbers, you'll see it at Finals too.

@ Schrummy
I'd support most of the load using a platform from the center console bump... then all-thread to the back wall.

Massive horns look cool and are really efficient, but getting their tuning just right is difficult. I'm working with "HornResp" but it's not really designed to work for car audio. I'm learning though.

Currently, I'm trying to develop tapped horn enclosure... which is kinda like a transmission line (tapered quarter wave tube [TQWT]). I've built a couple TQWT's but not for subs. They work well for full-range speakers (3" speakers that can boogie at 50-60 Hz).

schrummy wrote:

how would you support it????

as for the second..... angling it up is probably bad.... try starting at the bottom and have it horn out to a massive size....

could use some cables lol or just put some supports top bottom and sides ? i dont care much fopr the 2nd because with just two woofers ther eis no reason to have to port on top. and im not sure why its leaned so far back. NO one can honestly tell ya what will be better...

The idea was to minimize cabin space. Also, I didn't want to overdo the port area. Too much port scares the dB's away.

Crazy Box #3
It's alot like Aho77's old blazer... just not on fire.

The benefit to this box is REALLY easy tuning. By adjusting the port board length, placement of the rear wall, and height of the rear wall... all the tuning and box sizes are quickly available.

What is all the extra space behind it?


Seems like an intricate build for something that might not work

@ Skip,
The open space is just that... wide open space that doesn't get presurized.

I'm trying to decrease the cabin space, and create a more efficient shape.

Think about Rexs and S-10s. Small cabins pressurize easier. Making smooth transitions should help minimize losses. That being said, Crazy Box 1 is probably best... but Crazy Box 3 is easy to tune. Crazy Box 2 is somewhere in-between.


Sketchup makes everything seem complicated. Box 3 is just a flat board (wall) + 6 boards for the box + platform. Box 1 is an existing box, with a platform + 5 boards for the "orchestra shell"

what kind of car is this? looks like a suv? id almost be willing to bet you could get a normal box to play the same or louder all the way from the back. when you wall it up you really need to toss some cone area at it. walling with 2 10s in useless in my opinion.

It's the interior measurements for a RAV4 with no rear seats. B-pillar and back.

I'm at the point that Skip was describing in his other thread... where you're stuck at low-mid 140's and can't find the "sweet spot". I want to bring a decent score to Finals, but regular boxes aren't getting it done for me.

Alignments tried:
box in trunk - subs up, port up
box in trunk - subs front, port back
box in trunk - subs left, port right
box on folded down rear seats - CRX style
no rear seats, box non floor - CRX style

adjusted front-back, side-side, flipped, angled, etc

tuning has been anywhere from 37 Hz to 55 Hz.

Best scores were:
box on rear seats @ 45 Hz
box in trunk - subs forward port back @ 50 Hz (subs left, port right was actually the same score)


I know you gotta put time in... but as so many rappers have state, "Pimpin' ain't easy!"

it has a trunk?

RAV's have a normal SUV boot/trunk

have you thought about a differnt woofer and amp set up? im guessing most all your numbers testing the rear area were decently simular? are you using areos? and what size boxes? the size of the enclosure will play more of a roll than most anything youve mentioned testing

Pioneer mid-grade 10's. Have tested them for 1.0, 1.2, and 1.5 cubic feet each. They prefer 1.0-1.2 depending on everything else in the setup.

Haven't tried different woofers, since I can't imagine them being much different from Type R's or AQ SD2.5's. Amps are putting out rated +/- some... though they get toasty during SB runs.

Haven't used aeros yet, since there's usually plenty of port area.


Do you have any advice from successful Exploders/Blazers/etc... for SPL box design?

id forsure swap to areos. i think you would be suprised what a woofer swap might do

There used to be a Guy in a red eclipse that ran a 3 -15 box like box number two and he was in low to mid 150'z idle I'd agree with Alan though you should try aeros sub forward port back or sub up port back before u jump to the wall it takes a lot more build to make a wall l
oud

Thanks for the advice, guys.

Time to restrategize. Keep it simple, keep it efficient, and do work!

After some digging on Termpro,

Explorers and Blazers tend to do well with subs up, port to the driver's side. I'll give it a try this week, and hopefully find the sweet spot.

but you need to get some areos. i have pics of some boxes but didnt post them up.

With 2 subs, my Explorer always does best subs back, port side.

That should be easy enough to test. I'll make a box that can "DO A BARREL ROLL!"

then I can test:
subs forward/up/back and port left/right... that's 6 boxes in 1. yay!

This thread has saved me numerous hours of useless design work. Thanks guys!

chrisbaldelli wrote:

I'm trying to decrease the cabin space, and create a more efficient shape.

Think about Rexs and S-10s. Small cabins pressurize easier.

If that were always true, CRX's would be loudest with a wall. Are they?

Sometimes you have to learn the hard way, though.

As an engineer, I tried to maintain the hope that theory is worth poopy... but as you know very well SPL is illogical, except for that one truth:

"The only way to get loud is with a meter and a ton of hard work."