Digital Domain mastering engineer awarded U.S. patent

K-Stereo and K-Surround ambience recovery processing targeted for use in digital remastering of archival audio.
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The circuit designed by Bob Katz for the Digital Domain K-Stereo and K-Surround processors has earned a U.S. patent.

Bob Katz, inventor, author, mastering engineer and president of Digital Domain, has been awarded a U.S. patent for his circuit design, "Process for Enhancing the Existing Ambience, Imaging, Depth, Clarity and Spaciousness of Sound Recordings." As embodied in Digital Domain’s K-Stereo and K-Surround ambience recovery processors, the process helps recover lost or amplify hidden ambience, space and imaging, and generate stereo from mono signals without adding artificial reverberation. The system has proven extremely useful in creating 5.1 mixes for DVD releases of older films.

Digital Domain manufactures the rack-mountable DD-2 K-Stereo Processor unit with its K-Stereo process plus a two-band EQ and POW-R Dithering. The K-Stereo and K-Surround circuits have also been licensed to Weiss Engineering of Switzerland and Z Systems of Gainesville, FL. Weiss incorporated the patented K-Stereo process in the Weiss DNA-1, a high-end, multifunctional digital mastering device. Katz uses the Weiss DNA-1's noise reduction and ambience recovery features in his Digital Domain mastering suite. Z Systems features the K Surround in its z-K6 Stereo-to-Surround Processor. The K-Surround process takes the ambience in a stereo recording and spreads it across the surround channels, completely enveloping the listener in the recording's natural ambience, while the content remains fully mono-compatible.

In a career that spans four decades, Katz has recorded and mastered more than a thousand recordings, winning three Grammy awards. Katz's book, "Mastering Audio: The Art and the Science," is widely recognized and respected by educators, producers, A&R executives and engineers in the recording industry. Katz has designed several other digital audio devices, including the VSP Digital Audio Control Center and Jitter Reducer.

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