Surround-sound system with motion picture soundtrack timbre correction, surround sound channel timbre correction, defined loudspeaker directionality, and reduced comb-filter effects

Granted: Jun 22, 1993 Filed: May 28, 1991

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.