Patent US 4,332,979

Systems analysis approach to measure and to reconstruct the sound energy flux distribution characteristic of "live" situations. The present invention relates to a method of measurement of acoustical fields and the functional relationships in audio systems for enhancing the reproduction of sound. The environmental acoustic simulator is a system which generates at least two signals having different combinations of time delays from each of a stereo input signal pair and for deriving therefrom a set of not less than four output channels. At least forty five time delays at nonuniform intervals spanning a time period of not less than two seconds with different frequency equalizations are derived. Diffuse sound fields are created through electronic mixing and by the employment of not less than four loudspeaker groups. The sound fields generated simulate the reverberation typically observed in an auditorium, concert hall or cathedral, without distasteful interaction, or distortions, and provides full dimension and realism to sound by increasing dimension through reflections and emphasizing harmonic relationships nonexistent at recording. This provides greater aesthetic enjoyment of recorded music.