# Interesting if you need a lot of bass in a small space.



## btown (Jan 24, 2011)

I know that this is the 'home theater shack.' But it's not too difficult to believe that the same people who build home theater subwoofers may also build something for their car/boat/rv whatever. I built this subwoofer for my Scion XB. I didn't want to take up any cargo space, so here's how I properly fit a real 10" subwoofer under the passenger seat. (Amp is under the driver's seat.)
First I couldn't get enough internal volume using 3/4" MDF, so I decided to go with 1/2" MDF, but the cabinet is so small and odd shaped that it is very stout. I can assure you that it doesn't vibrate/resonate and the 1/2" MDF got me to 0.55 ft³ of volume. 

Here's the google sketchup of the box.








As you can see, the box has plenty of intersecting edges that act as external braces. They are purely there for function. I had to extend out in every place I could to get the necessary airspace.

A test fit.









The finished product. 








I used 'Herculiner' paint on bed liner to cover the box. There was no good way to carpet the box with all the odd corners. It was down on the floor where it would get kicked around, so this was the best option. You simply stir it up and paint it on. It is textured so it does a great job covering up seams and screw holes. Also, it isn't sparkly, that's the flash reflecting off of it. It generally looks like, well spray on bedliner, but you can pick a can up at the auto parts store or amazon and finish a cabinet for really cheap and it looks good. Not like veneer good, but it looks finished and professional.

Another angle.









With the sub mounted.









And the final fit under the seat. 

















Lots of deep powerful bass, and not a bit of space lost. The passenger gets an almost bass-shaker like experience. 

I know this isn't the place for car audio, but I thought everyone could benefit from seeing the Herculiner covering. It's super tough stuff, that goes on thick and makes an impermeable shell. If not for the subwoofer, you could hose off the box if need be. Also, that 1/2" MDF or plywood makes a plenty stiff box if the panels are adequately braced or small enough.


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## Mike P. (Apr 6, 2007)

Nice job on a custom fit sub. :T Was the Herculiner a roll on product?


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## btown (Jan 24, 2011)

Yup, it's roll on or brush on. It's pretty thick, but really easy to apply, I used a cheap paint brush and did one or two coats to get it into the corners.


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## dougc (Dec 19, 2009)

Very nice and way to be creative with your space - Good bass in a vehicle is difficult without using up good storage space and keeping stealthy. I just built a shallow enclosure for under the rear bench seat in my F150 and finding a good sub with 4.5" mounting depth was difficult without spending a fortune. I'm having the amp installed Monday and can't wait to finally hear it.


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## blackzarg (Apr 19, 2009)

Wow! This is really cool! Where can find more info on this, parts, etc?

I would love one in my civic...


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## btown (Jan 24, 2011)

http://www.crutchfield.com/p_130TSS2501/Pioneer-TS-SW2501S4.html?tp=111

Pioneer TS-SW2501S4
10" sub that I remember sounding pretty good for fitting in a tiny box.

0.35 cubic feet is only 12" x 12" x 4" internal volume.

I went with the Boston Acoustics G210-4
http://www.crutchfield.com/s_065G2104/Boston-Acoustics-G210-4.html?tp=111

It sounds great, but need 6.5" of depth. Most passenger cars probably don't have that under the front seat.

The first step is pulling out the tape measure and seeing what fits, maybe grabbing some cardboard boxes and seeing what you can shove under the seat and how much room you have to work with.


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## Gregr (Nov 2, 2010)

Nice! I like the Hurculiner idea. My first thought would have been fiberglass..., which is probably why I haven't got a sub in my car, yet. I've got an New old stock Caustic amp and a nice Focal 8" sub speaker and every tool I need. But I hadn't put it together until reading your post. 
This project will have to wait until late spring but I thank you for for the idea!!!

Greg


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## Zeitgeist (Apr 4, 2009)

That's nicely done, especially with such a tight fit!


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## the_abbot (Jun 2, 2010)

Awesome build man!


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## shio1983 (Apr 17, 2011)

Great build, very nicely done, just go for another under the other seat.


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## Hunter844 (Apr 22, 2007)

Great build, I may look at this for my truck...not happy with my current sub. Is there a sketchup for idiots program to help me design the box or do I just have to calculate the box myself?

Does Box Notes work with car audio?


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## Gregr (Nov 2, 2010)

Hey,

I just have to say in my own defense..., "Not everybody drives a heavy metallic silver painted Honda with the sub in the trunk, like the honda I hear every day from the other side of the river (about .75mi away, but I exaggerate a little) ".
Having a sub in the middle of a speaker array is close to where it needs to be. Car environments are difficult if you know what your doing..., I don't but I sense a sub under the passenger seat is close. I will try it.

If you hear a slight rumble as I drive by its only because you cannot hear the mids and tweets thru the sound proofing in cars .

Greg


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## BETO (Dec 31, 2010)

whats that material you are talking about? can you please tel me in spanish? whats that black paint? i work with stereos and im llearning about car audio.. but some problems i dont under stand what you talk about can any one help me to use the rew program? im in mexico and i dont speack english so much.. please help.. this is my e-mail.. [email protected] thnks


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## WyoChris (May 23, 2011)

Nice utilization of available space. Let us know how the herc holds up for you. It is a durable finish but when I used it, as truck bed liner, it uv bleached out really badly.


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## Loudy (Apr 5, 2011)

Nice box. I had the same problem in my truck. I ended up using a Stereo Integrity BM MKIII under my rear seat in a tiny box also coated with a similar product. I prepped both boxes and used Rust-oleum Spray Rubberized Undercoating. It takes a while to off-gas but is very durable and doesn't look bad for a quick and cheap finish.

Here are a couple of pics of the truck box with the coating and I used it on a couple of monitors I built for my PC as well.


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## bawward (Feb 2, 2012)

Interesting idea. Ever consider fiberglass? Also, you sure you don't have any excursion interference when someone sits in the seat? Phew that's close!


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