AudioFred Messages: 377 Registered: May 2009 Location: Houston
Illuminati (1st Degree)
The tweeter also needs to be inexpensive. Forget about ribbons or horn-loaded compression drivers. Any good one would be too expensive. Enter the Vifa XT25. Low resonant frequency, high sensitivity. It also has a reputation for being very robust, and important feature for a tweeter that must match twelve woofers without breaking a sweat. Here's the array with the XT25 and a third order crossover (electrolytic caps, of course, because it must be inexpensive). I also experimented with tweeter attenuation resistors and found I like a 1.5 ohm resistor ahead of the tweeter crossover, which is included. The tweeter caps are a 15uF and a 31uF. The inductor is a 0.15mH. The woofer array is wired directly with no filter.