I made some speakers when I was in high school. The tools I used were a table saw, a whole bunch of long clamps, a screwdriver, and a hand drill. But most important, this book: http://www.amazon.com/Building-Speaker-Systems-2nd-Edition/d... . If you buy it used now you will find it hilarious how they describe using computer software to analyze speaker systems, but no matter: you can stand on the shoulders of giants and design your own boxes without any software at all.
The "D'Appolito array" is covered in that book--a design employed in many store-bought speakers where two mid-woofers flank a tweeter at a specific distance to avoid some of the time alignment concerns raised here. This is a good candidate if you want to build smallish, narrow speakers for home. In the car it usually comes down to "where is there enough room for the drivers I want?"
I think the book also discusses various dual-driver arrangements for subwoofers, which is another interesting area where you can use twin drivers to eliminate undesirable effects. If you put that together with the D'Appolito design in a single cabinet, you will have something like what Infinity used to sell for $1000 each...but doing it well won't save you much money because good drivers are expensive.
The "D'Appolito array" is covered in that book--a design employed in many store-bought speakers where two mid-woofers flank a tweeter at a specific distance to avoid some of the time alignment concerns raised here. This is a good candidate if you want to build smallish, narrow speakers for home. In the car it usually comes down to "where is there enough room for the drivers I want?"
I think the book also discusses various dual-driver arrangements for subwoofers, which is another interesting area where you can use twin drivers to eliminate undesirable effects. If you put that together with the D'Appolito design in a single cabinet, you will have something like what Infinity used to sell for $1000 each...but doing it well won't save you much money because good drivers are expensive.