http://www.royaldevice.com/custom.htm#THE%20REAL%20TOTAL%20HORN

LITERAL:
The Biggest SUBWOOFER of the WORLD, for the most esoteric Audio and AUDIO-VIDEO Room of the World. The Highest efficiency ever obtained with NO hearable distortion using NO feedback tube low power amplifiers and NO crossover on the speakers. To understand how this is possible, you can read all thruout the WHITE PAPERS, here you wil find the answers to all your questions.

Fuente: Music Thing