View Full Version : NEW IDEAS...will pay for box design, TIGHT SPACE, real help needed.

09-08-2011, 12:38 PM
Hello IDIOTS!!!

JK your all smarter than I that why I need help.

I am looking to put TWO 15 inch MEMPHIS mojos in my trunk, I have one now.

I have a VOLVO S60 which has quite a bit of trunk space BUT the dimensions of which are funny, and the trunk opening is small which LIMITS the available room to work with.

Let me tell you what I have done previously:

I have built two separate boxes, which was the only way I could feasibly fit two ported sub boxes into my trunk, these boxes were for two kicker L7's.

Their dimensions were EXTERNAL: 31 X 15.5 X 13. I was unable to fit a single large box in my trunk due to the slope of the trunk opening and the available opening width.

I sold the L7's and NOW I have built a SINGLE box for my memphis MOJO 15. It fits in, but BARELY. I had to kick it LITERALLY kick it the last coupple of inches to get it in my trunk. The baffle was chipped as a result, The baffle is 2x think MDF so I don't think it matters much.

THe external dimensions of this box are:

30 X 16 X 21.

THere is available space on either side of the box when it is inside my trunk BUT the trunk opeing just doesn't allow me to get any larger of a box into my trunk.

The hinges of the trunk are NOT a problem as they are outside of the trunk cavity.

I will include pictures to show my dilemma.

Trunk opening:


Back seat into trunk:


As you can see the available trunk space is ample, the ability to insert the box into the trunk is LIMITED.

again for DUAL Mojo 15's

09-08-2011, 05:51 PM
Looking at it I see a lot of cancellation. Their facing each other and the sound waves can go to the front and back of the car and cancel web more when the rear come back forward. The only thing I can suggest is making the box inside the trunk

Or what u can do is make the box in 2 parts (top side back, then other side front bottom) and then use weather stripping to seal with screws so that way it's still pretty dam air tight and u can still take the box apart and pull it out without cutting the box all up and making a new one lOl

Bettr n' Revrse
09-08-2011, 05:52 PM

ideal concepts
09-08-2011, 05:55 PM
What is the size of the rear seat opening, maybe u can get a box in that way.

09-08-2011, 06:17 PM
The rear seat opening is 15 tall in the center and slopes off to 14 then slopes again cutting our square corners.

THE trunk opening is 16 if i remove all the surrounding castings and such.
But it too has slopes and dips down to 15 on either side and further decreases usable entry space becasue of corner rounding.


ALso I don't have this dual box setup any more.

09-08-2011, 06:30 PM
build it in the trunk. there is a tool called a pocket hole jig that you will need todo it right

09-08-2011, 06:41 PM
What is the width of the trunk opening?

If you could fit a box thats 35wide in, you could go 14high and 30 deep to get 6.9 cu/ft to work with. Then subtract port, woofer and bracing displacements to get the final volume the woofers will see.

09-09-2011, 05:52 PM
the opening is funny, it will permit boxes that are 30 wide IF the box is also shorter than 16 tall.

The trunk will allow 31 if the box is less than 15.5 tall.

the tunk will allow 34 inches is the box is less than 14 tall.

these variances are all attributed to THE CURVATURE of the trunk opening and the NON 90 degree angles are REALLY TRICKY!!!!

Also the trunk will allow upto 20.5 inches depth if the box is 16 tall

The trunk will allow a box that is 32 deep if the box is LESS than 15.5 tall.

DUE TO THESE reasons, that why i decided initially to do a dual box for my dual 12's.

The trunk space is tricky!!!!

thank you for all of your input.

09-09-2011, 06:38 PM
35w x 13h x 32d is 6.79 cu/ft assuming .75in thickness

I use this site alot for calculations:

Subwoofer Enclosure Calculators, Fraction to Decimal, Parallel, Series, Port Length and Volume Calculators (http://www.the12volt.com/caraudio/boxcalcs.asp)

Bettr n' Revrse
09-09-2011, 06:40 PM
Why you no do IB?!

09-09-2011, 07:10 PM
Not sure how to.

My trunk houses my amps and battery and fuses under the floor board. kinda imperative that I get to those too.

:_( are my dreams too big?

Bettr n' Revrse
09-09-2011, 09:33 PM
Not sure how to.

My trunk houses my amps and battery and fuses under the floor board. kinda imperative that I get to those too.

:_( are my dreams too big?

What? No no... Infinite baffle lol


09-09-2011, 10:14 PM
OH SHITTTTT forreal?

I dont know how to calculate that?

WHat is the output like?

If by doing so I would get less or similar output, this this concept would not profit me, realistically probably just waste money LOL.

IM all ears, tell me MORE!!!!

09-09-2011, 10:20 PM
I really do appreciate the suggestions but I wouldn't be able to fit that box into my trunk.
the maximum i can do width is 32, but that is if i skimp on height, which I see that you have calculated for.

I guess I could mount the subs upward facing the sky?

BUT then I would be SCREWEDD!!!!! IF I even need to change the battery or had a flat tire, that thing would be heavy!!!!
Any conceivable way of getting around that ?

Bettr n' Revrse
09-09-2011, 10:20 PM

Well ff you are going for a ton of output then its probably not for you... Not saying with 2 15's you wont get quite a bit however...

09-09-2011, 11:54 PM
What motors do you have on the memphis cones?

I gues my real question is would converting to this type of setup loose SPL or SQ?

How is this design tuned?