The acoustic curtain idee: One Microphone provide the signal for each assigned speaker on the other side of the wall. Like a curtain the loudspeaker wall restores all wave fronts entirely by that way, long lines would make the perfect reproduction. This idea is not new. Such broadcast was the dream of the scientists in the 30th of last century alredy, but was consider utterly impossible because of the number chanels was out of reach by far. By wave field synthesis principle become possible the realization today.