DIY Subwoofer box that doesn't sacrifice the footwell! - 986 Forum - The Community for Porsche Boxster & Cayman Owners

I've been searching for some time for a subwoofer solution but have not been able to find anything I liked, so I decided to build it myself. I was fortunate enough to have 3 Focal 5" subwoofers given to me by a relative, but my design could definitely be modified to fit a shallow mounted 8" subwoofer as well. I found that footwell mounted solutions as well as trunk mounted subwoofers were too intrusive. The seats are not high enough to fit a sub directly underneath, not to mention that the front/ rear adjustment bar would hit a box if you try to use the full width between the seat rails. My solution: I made a box that mounts the driver behind the seat, but wraps around below the seat as well. This gives the box extra volume (about .33 cubic feet in my case) without making a box that is too deep (restricting rearward movement) or being too high which restricts your seat from reclining. I made the box out of MDF and fiberglass (for the back) and painted it black to match my exterior. Note that I angled the box under the seat which allows the seat to be lowered down somewhat.

Look on renntech.org There is a guy there who builds boxes for a 8". I have one on order from him. A1 quaility...

Is that the rear deck option? I didn't want to give up the storage space because I have the factory windstop. Also, his is running about 200 watts and mine is running about 500. This option you can make yourself easily. His design also looks more prone to flexing under driver loads.

so how does it sound?

and how much do you want to build another? PM me please.

Does it limit the movement of the seat???

The rear deck im running will see about 500 watts... as for flex I doubt it. Ill let you know when mine comes in..

It sounds great! I had to turn down the gain on the amp to prevent the subs from overpowering the system. My box doesn't have much flex, but I also just wanted a sub to fill in the bottom end, rather than pound and annoy those around me. Its much more bass than I expected, but it still needs to be tuned. The way I built mine, I lose about 1.5" of space, maybe about an inch, but I found that acceptable. I can make it differently so it does not interfere with the seat, but It would have required making it slightly higher which I was not willing to do. I'll try to get more details up after my final installation. I have a multi channel amp going into the front trunk next week and I need to make a panel cover to go overtop of it. With respect to flex, on a larger sub with high output, I've seen bigger boxes flex noticably. If you want to avoid that, you need to really build up the fiberglass which adds weight, and I wasn't willing to do that. A box with a .5 cft volume can easily be 15+lbs. I figure mine is about 10.

15lbs doesn't bother me especially with the extra 100 or so hp I've added.

Looks Nice But You Still Lost Some Rear Seat Travel I Had The Same Setup For Years Before Builing A Box For In Front Of The Passenger Seat With Dual 8" Woofers Set At A 45 Degree Angle The Space Just In Front Of The Seat Is Wasted Space Anyhow. Sit In The Drivers Side And See How Much Room Is Wasted Under Your Legs-unless You Have Really Short Legs Your Leg Just Rests On The Woofer Metal Screens. Lots Of Ways To Cut Bait With This One!!

I did lost about 1.5" on this box, but if you pull the sides in behind the rails, you can do it without losing any room at all. Having said that, I have friends who are well over 6' and they still fit comfortably in this position. I didn't want something visible because then you can attract thieves.

Please post the link. I'm interested in seeing what it looks like...

I've seen and heard Justin's set up at a PCA event and it's the real deal! Kind of hard to see from his pictures, but it really doesn't restrict seat travel at all. Great design and the sound really seems to fill the cockpit. J: I still think it would look awesome if you could cover in factory colored carpet! For me, I put the biggest Bazooka Tube I could buy in the frunk (10" x 250w Class D Sub). You can definately hear it, but overall I'm disappointed by the end result (unless I'm parked and the hood is up = hardly ever). Plus I often get vibration off the hood and look like a dork at stop lights.

Just wondering where one takes the audio line from to feed the subwoofer amp? Much thanks. Don Wilson

You can either use an aftermarket head unit with RCA preouts or you can use a line-out converter from the factory amplifier in the front trunk (sorry I refuse to use the word Frunk).....oh dang I used that word.

I also have the stock windstop, but with the bose factory "stuff". No storage for me to begin with, but I have a buddy that says he'll make me one for shallow eights out of fiberglass for $125.

This is what I have put just behind the seat. £140 on eBay, £180 in the shops In Phase USW10 features * Maximum Power Output 300W * Rated Power Uotput 100W * Output Impedance 4 Ohm + 4 Ohm * Crossover Frequency 50-100Hz * Size: 270mm (diameter), 69mm (height) * Weight (inc accessories) 4.8kg * Phase Button (0-180 degrees) * Remote level Control (5m) * Aluminium Cone * Ultra Slim Design * Die Cast Aluminium Chassis

Anyone make a thin single 10 inch sub box for behind the passenger seat?

I would also be interested in something like this.

I was thinking maybe just trying to take a 10 or 12 inch FREE-AIR Subwoofer, mount it to a thin piece of flat wood and just lean it as far back behind the seat. any thoughts on this?