The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 26, 1994
Filed:
Jan. 14, 1993
James K Waller, Jr, Lake Orion, MI (US);
Rocktron Corporation, Rochester Hills, MI (US);
Abstract
An audio sound system decodes from non-encoded two-channel stereo into at least four channel sound. The rear channel information is derived by taking a difference of left minus right and dividing that difference into a plurality of bands. In a simplistic implementation, at least one band is dynamically steered while the other band is unaltered so as to avoid any perceived pumping effects while providing transient information to left/right, as well as directional enhancement. In a preferred embodiment, multiple bands are dynamically steered left or right, so as to enhance directional information to the rear of the listener. In both schemes, the low pass filtered output of the sum of the left and right inputs is also combined with the directionally enhanced information, so as to provide a composite left rear and right rear output. Furthermore, the center channel information does not necessarily require a discrete loudspeaker, and can be divided so that low frequency information can be applied to the rear channels while mid and high frequency information from the center channel can be applied to the front left and right channels to compensate for any perceived loss of center information.