How would you build an active subwoofer for your home theater using a car amp and subwoofer speaker?

Answer 1

The key to speaker construction is the design of the enclosure. You have to have a good speaker and an appropriate amp, but there are a bunch of variables associated with engineering the cabinet or box you build the whole thing into that you'll have to figure out. And a lot of them will depend on the speaker you are using, specifically its acoustic characteristics. The bad news is that there are whole books on the subject of speaker design, and that means you have your work cut out for you. There is a lot to learn and know. If you're interested in learning stuff, go for it. If you're interested in short cuts, it is far cheaper to buy one than build one. If you build one without really "doing your homework" first, its performance has a great chance of being far less than satisfactory. (Poor research = sound that sux.) You'll almost certainly waste your time and money going for a shortcut solution. (You will probably end up going out and buying one later.) As an aside, using a car amp will require you to come up with a "12 volt" supply to drive it. Active subwoofers for the big Home Theater systems plug in the wall (or have an adapter). That's just one more issue you'll have to deal with if you "do it yourself" using the car amp approach. There are subwoofer enclosures for car sound systems that you might buy or build that could give you modestly good performance. Generally, however, they won't perform as well as the "regular" middle-of-the-road home units. Check out stuff at your local car sound systems vendor. Good luck.