Should I be thanking an '80s TV show for my new subwoofers? I suppose so. Some months back I made a mental note - whenever out shopping always be on the lookout for a vessel/container that would make a decent subwoofer. Either something attractive, or something cost-effective and easy to work with. A couple of days ago, while in Home Depot, I saw it. A 'Sump Basin
' - 20 gallons of rigid-walled goodness. I figured it could substitute for a length of sonotube, perhaps it would be easier to work with. When I saw the Sump Basin (SB) what caught my eye was the provision for four bolts on a reinforced rim, plus the rigidity of the unit - this is no garbage can, it is stiff-walled. Of course the other thing that caught my eye: The price - $23.
That price is low enough to make this project come in under $300 - for all parts and supplies - for a pair of decent passive 12" subwoofers that took less than an hour each to put together and which perform perfectly from the get-go. They are not pretty, but that can be fixed.
Intrigued by the SB's potential, I biked on down to home Depot and picked up a pair of basins, a 2'x4' sheet of 3/4 birch plywood (cut in half), some fence-post toppers, bolts, felt pads and duct putty.
Before I go any further - listening to just one of the completed subs last night, my wonderful
wife Danya became concerned while we were re-watching "Big Trouble in Little China" for the gazillionth time. She was afraid the bass during the 'green lightning' scene at the brothel would cause structural damage to our house. That's a first, and she's been with me for a couple of decades worth of excessive noise-making. That's using the same drivers, in the same place, at the same amp settings as before. The main thing that changed is the subwoofer's housing.
My woofer of choice lately is the Sony Xplod XS-GTX121LW
. Ignore the fact you can only buy this model at Wal-Mart - it is quality, especially for the price. It has more features and is better sounding than Kicker CompVR, Polk DXi and Alpine Type E 12" subs, all of which are sold by big-box stores and all of which I've owned. My current system contains six of them... four doing full-range woofer duty on my mains and a pair working as dedicated subs. That said, this design would work with any 12"sub that feels comfortable in a sealed configuration with 2.5 cubic feet of air.
The first step in assembly - marking the holes for the bolts on the baffle:
Step two - drawing the hole for the cut-out. Sony was nice enough to package the subwoofer with a piece of cardboard that acts as a perfect template for the cutout:
I used a jigsaw to cut the hole. Quick check to make sure the sub fits:
Next step is to cut a hole and install the wire terminal as well as the sub itself. Duct putty is used as a sealant on both the subwoofer and the terminal: