To meet my low end extension goal, I knew that I would need to use a ported enclosure for the woofers. For the maximum in low end extension, two of these woofers would need a very large eight or nine cubic foot enclosure. My concern was more about output and thump in the 35- 50 Hz range, so I decided to use a much smaller enclosure tuned to a higher frequency. I settled on shooting for roughly a 4 cu. ft. enclosure, tuned to 30 - 40 Hz. When it comes to trying to maximize power handling and bass output for a speaker like this, I find that tuning in the 30 - 35 Hz range provides the best results. Since the midrange driver I selected is a standard open-back woofer, it needs its own sub-enclosure. From an ease-of-construction standpoint, I decided that a 7" internal square running from the front to the rear of the cabinet would be very simple and provide ample driver room. This yields about a .35 cu. ft. sealed enclosure for the midrange, which is sufficient to keep the resonance peak low in frequency and magnitude. The overall cabinet dimensions are 46" tall, 16" wide, and 14" deep. Dual 3-3/4" x 7-5/8" ports provide a tuning of approximately 34 Hz.