Dakota Audio manufactures full range directional speaker arrays. For over 10 years, the leader in focused sound with installations in over 75% of the museums in the USA. Mini line arrays (1"x1"x18-38") Overhead arrays, and walk on floor speakers less than an inch thick. The only user configurable directional sound system on the market with adjustability for distance to focal point, area of coverage, proximity detection, ambient noise level compensation, and both a hardware and software configurable interface. Not an ultrasonic solution. Simply the highest quality sound reproduction of any directional speakers at very competitive prices.