I finally bought a router and built some nicer looking speakers. I don't know what took me so long to learn how to use a router, they add a nice finishing touch. These are made out of solid oak project boards from Home Depot, rounded the edges over and flush-mounted the drivers (Jordan JX92S full-range). They are the MLTL 48 transmission line design, although the cross-sectional area is a little too small.
Sound great, though, much more bass than the previous set of speakers, and they can be driven at more realistic volume levels.