Michael L. Dorrough
American audio engineer
Michael L. Dorrough (born January 1942), American inventor and audio engineer regarded as the “father of multi-band processing.” He is the founder of Dorrough Electronics and inventor of the Discriminate Audio Processor (DAP) in 1973, and the Dorrough Loudness Monitor. While the DAP product instantly changed audio processing in the broadcast world, the company is best known for its award-winning “eyebrow” scale audio loudness monitors in widespread use throughout the motion picture, recording and broadcast industries worldwide.
Biography
Born in San Francisco. Began his career as a recording engineer in 1963 at Casey Kasam and Bob Hudson's Emperor Productions. While focusing on recording, he maintained working relationships with several of the Los Angeles radio stations, bridging the gap between the two mediums, which enabled him to experiment with audio processing.
Later at RCA, he continued his research on his theory that audio processing should be directed toward perceived power and not on amplitude alone. The first composite tri-band processor was incorporated into the recording sessions of such artists as Jefferson Airplane and Carol Burnett. In 1970 Dorrough Electronics was formed to market this product.
Aware of the inconsistencies in the metering of program levels, he realized that to maintain consistent listening levels that there must be a relationship between the peak and the average content, and that both should be displayed on a common scale. His development of a LED meter displaying both peak and average ballistics with dual reference points is used for audio program level indications throughout the world.
“Michael L. Dorrough” enters the record as american audio engineer. Crown Archives preserves that source wording while asking what Michael, Dorrough and American can confirm, complicate or overturn.
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Biographical claims are most persuasive when dates, appointments and relationships can be traced to records created close to the events described. The source revision retrieved here is dated Dec 3, 2025. The linked authority identifier is Q18001518. None of the 2 selected statements returned an explicit reference. The first chronological checks are 1942, 1973, 1963 and 1970.
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This entry incorporates text from “Michael L. Dorrough” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.