The Design of Encoding Functions for Stereophonic and Polyphonic Sound Systems

Recordings of live performances are often made using coincident microphones, which encode directional information into two or more channels. The accurate reproduction of the performance is dependent on the encoding functions implemented by the coincident microphones. The design of encoding functions is developed for stereophonic, full surround (ambisonic), and semicircular surround systems. An optimum stereo encoding is developed, a family of encoding functions is derived for the ambisonic system, and a method for deriving the optimum encoding functions for semicircular surround systems is introduced.