Stereophonic signal processing circuit
Patent 4841573 Issued on June 20, 1989. Estimated Expiration Date: 
August 29, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
August 29, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesMatrix four-channel decoding system Surround sound system Triphonic sound system MOSFET analog signal squaring circuit Three-track sterophonic system Patent #: 4747142 InventorAssigneeApplicationNo. 07/237986 filed on 08/29/1988US Classes:381/27, Center channel381/106With amplitude compression/expansionExaminersPrimary: Isen, Forester W.Attorney, Agent or FirmInternational ClassesH04S 5/00 (20060101)H04S 5/02 (20060101) H04S 3/00 (20060101) Foreign Application Priority Data1987-08-31 JPAbstractA stereophonic signal processing circuit is designed to be provided with a pair of level compression circuits compressing peak levels of a pair of stereophonic input signals into 1/2 power each, an arithmetic mean circuit determining an arithmetic mean between a pair of output signals issued from the level compression circuits, and a level expansion circuit expanding a peak level of an output signal from the arithmetic mean circuit into the 2nd power of the level so that an output signal from the level expansion circuit is reproduced midway between individual reproducing positions of the pair of stereophonic input signals. A delay circuit may be connected between the arithmetic mean circuit and the level expansion circuit. The stereophonic signal processing circuit makes it possible to cause more fully the lateralization of a reproduced sound and can be fabricated at a low cost. | |
