DIY Subwoofer box that doesn't sacrifice the footwell!
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.
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.
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.
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.
------------------------------- '01 Boxster S
Just wondering where one takes the audio line from to feed the subwoofer amp?
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.
Lov'n my boxster!
2013 Lexus IS350awd
2007 Toyota FJ Cruiser
2004 Porsche Boxster S