ORIENTED ACOUSTIC SYSTEM Russian patent published in 1997 - IPC

FIELD: directed sound emission. SUBSTANCE: device has loudspeaker which is located in concave reflector which has inner wall which is made from material with low sound absorption index, external wall 3, which is made from material with high sound absorption index, and elastic sealing insertion which is located between them along perimeter of their connection. Rough vacuum is provided inside reflector. In vacuum mean free path of molecules is by 1-2 mm greater than minimal length between walls. In addition electric transformer which has two windings is located inside reflector. One winding is located on inner, another one on outer wall of reflector. Wires to said windings of transformer is provided through sealed holes on walls of reflector. EFFECT: increased functional capabilities. 2 cl, 1 dwg