MTM Section: I used the Dayton RS180 midwoofers, the Seas H1212 tweeters in a MTM configuration. The 1.1 cu. ft vented box is tuned to a F3 of 51 Hz. The crossover is a 4th order LR at 1,800 Hz with an zobel network and a 3 dB baffle step compensation network. I don't like the sound of a full BSC due to boominess, so a half BSC suits me fine. As you can see from the frequency response plot, there is a rise from 10KHz to about 4.5dB, but the response is quite flat at a 30 degree axis. I left the tweeter as is and did not pad it down, since each tower stands about 13 feet apart. At a sitting position in between the MTMs, the response should be flat.

Subwoofer Section: I used the Dayton RSHF 10" subs in a 1.5 cu. ft. box, tuned with 12" passive radiators, the Dayton DVC PRs, with 255 g of added weight. I used washers and a nylon lock screw to secure a number of washers to the PRs. Predicted F3 is about 25Hz, and bass quality is outstanding.