To my 17 mids/20 tweets per side, I'm thinking of adding a NSB type mid woofer array. I could go to 7 inch Dayton Aluminum mid woofs, but they are about 16 bucks each and the cost would pretty much limit me to 3 per side. I'm thinking more in the way of the Audax 6.5 AP170MO That Madisound is selling for 10.50 each, where I could put in 5 per side.The electronic crossover(24 db L/R) here is around 500hz, and I may let them drop off naturally, or turn on the 50hz 12 db filter in the electronic crossover.
A sub woofer takes over at about 100.
5 per side gives a real array with all the benefits of an array.
eric j.