Keith O. Johnson

US recording engineer, born March 29, 1938. In the 1970s, he worked with rock band Ambrosia (2) and partnered with producer Alan Parsons to develop the Projectron, one of the first tools to incorporate expressive polyphonic sampling, used on I Robot. In 1976, he joined producer J. Tamblyn Henderson, Jr. and Marcia Martin to form Reference Recordings, launching a legacy of high-end/half-speed mastered LPs and high-definition CDs (DDD). Co-invented the HDCD technology with Michael Pflaumer and in 1996, they formed Pacific Microsonics to introduce the concept of high-resolution audio. In 2000, Microsoft purchased Pacific Microsonics and continues to incorporate HDCD technology into its PC offerings. Prof. Johnson subsequently consulted with Microsoft; one project, Speaker-Correction, uses modeled correction of speakers to improve computer sound and can be found in XP software.