Better Bass Cheap and Easy: Build a Cardboard Subwoofer!
Build your very own high quality sealed subwoofer in just a fraction of the time it would take to build a traditional box. It's all about Sonotube, the toughest cardboard you'll ever meet!
Getting great a low frequency subwoofer usually involves a lot of cash, or spending a lot of time building up a box.
And even sealed boxes, the simplest subwoofer enclosures, can be a pain to build. So when we wanted to sample several box sizes fast, we picked up some Sonotube. It's a type of concrete form used to make columns... but with some plywood and a little routing, and a lot of glue, you can quickly sample several sizes of subwoofer enclosure.
It all started with Patrick's desire to get some decent low end bass in his truck... and a stop by the epic Pass DIY web pages, where he read about The Legend of EL PIPE-O, Nelson Pass' massive subwoofer experiment that sported 8 21-inch drivers and a pair of 12 foot hight Sonotube concrete forms.
Sonotube makes subwoofers quick and easy to build by eliminating a lot of saw cuts and joints. It's available in sizes from 2.25" to 36.90" and easy to cut to length... just head on over to the Enclosure Volume Calculator at HomeTheaterShack.com or the Subwoofer Enclosure Calculators at the12volt.com and play with the available sizes you want with various lengths until you get the volume of enclosure you're looking for. (Betwen .5 and 1.5 cubic feet in our case.)
Why sealed? In theory, tho they don't have the over the top boom of ported boxes, sealed subs have the most accurate audio response. They're also the easiest enclosures to design and build. Most important, HSU Research's ASW-1203 was designed for for a sealed box. That's Patrick's pick to go into his beloved truck.
Along with a subwoofer and Sonotube (sold by the foot at most hard core building supply places... ask them to cut it to the length you want if you don't have a tale saw at home) you'll need plywood or MDF for the end caps, glue, and at least a pair of clamps... tho a half dozen Jorgenson Pony pipe or Irwin Quick-Grip Bar Clamps can make the glue up go a lot faster!
You can use just about anything to cut out the hole for the Sonotube... but a router with a circle guide or a jigsaw will work a lot faster than any kind of hand tool.
To finish your subwoofer off, you'll need some polyfill pillow stuffing from the local crafts store, a terminal plate to attach your speaker cables too and some wire and connectors to attach the sub to the terminals.