Page 78 - Spring2022

Obituary
Mahlon Daniel Burkhard, 1923–2021
Mahlon Daniel Burkhard, chairman of the board of HEAD acoustics, Inc., Brighton, Michigan, died on August 26, 2021, in Adamstown, Maryland, at the age of 98. He was born in Seward,
Nebraska, on January 14, 1923.
Mahlon’s dedication to acoustics for more than 70 years may have begun during service in the US Navy Pacific Fleet in 1943 as a landing craft pilot delivering US Marines to the beaches of Iwo Jima and Okinawa. He was in a craft less than 1,000 feet from the battleship USS Missouri when it fired its 16-inch guns over him, causing partial hearing loss and distortion in one ear for the rest of his life.
After his military duty, Mahlon finished his undergradu- ate degree at Nebraska Wesleyan University, Lincoln, and then received an advanced degree in acoustics from The Pennsylvania State University, University Park. He began his career at the National Bureau of Standards in Wash- ington, DC, helping to establish the first standards for hearing aids. He moved into private industry as director of research at Industrial Research Products in Elk Grove Village, Illinois, heading teams developing and commer- cializing the Knowles Electronic Manikin for Acoustic Research (KEMAR), a line of digital audio signal-delay products, and multiple studies of electret materials and processes for electret condenser microphones. Under his direction, the communication microphones for the NASA Apollo lunar program were built.
Mahlon made many contributions to both the American National Standards Institute (ANSI) and International Electrotechnical Commission (IEC) standards committees, was a chair of the Engineering Acoustics Technical Com- mittee of the Acoustical Society of America (ASA), and was active on the ASA Committee on Medals and Awards.
The 1972 development of Mahlon’s digital signal delay was at the outdoor music pavilion at Ravinia, Highland Park, Illinois. Tests were performed in a long tunnel beneath the facility, using a speaker and microphones.
Prototype delays were timed according to these tests and refined by listening.
That work began a long collaboration and friendship with Christopher Jaffe, the Ravinia acoustician. Jaffe challenged Mahlon to develop multitap nonrecursive delays as reverberators, extending the natural reflection character in performance spaces. Their first installa- tion was for the 1980 NBC television series Live from Studio 8H featuring the New York Philharmonic under the direction of Zubin Mehta. Jaffe used Knowles elec- tret condenser microphones flush mounted into stage ceiling reflectors there and in other concert spaces to feed “electronic reflected energy” systems (ERES) and produce “electronic forestage canopies” where physical ones could not exist, for example, the acoustic renovation of the Oakland Paramount Theater, Oakland, California.
Throughout his career, Mahlon was awarded seven patents and made many significant impacts. He attempted retirement in the late 1980s but immediately moved to Connecticut to work with Jaffe on performing arts electroacoustic systems and become president of Sonic Perceptions, Inc., Norwalk, Connecticut, the new Jaffe Acoustics-owned firm that intro- duced HEAD acoustics GmbH binaural technology to North America. Mahlon retired again in the mid-1990s to become chairman of the board of HEAD acoustics, Inc.
He was preceded in death by his wife Charlotte and son Douglas. He is survived by his sons John, David, and Ronald; five grandchildren; and three great-grandchildren.
Selected Publications of Mahlon Daniel Burkhard
Burkhard, M. D. (Ed.) (1978). Manikin measurements. Proceedings of Conferences Organized by M. D. Burkhard, Industrial Research Products, Inc., Elk Grove Village, IL, Zurich, Switzerland, March 4, 1976; Washington, DC, April 5, 1976. Available at https://www.grasacoustics.com/files/m/a/KEMAR_Manikin_Measurements.pdf.
Burkhard, M. D., and Corliss, E. L. R. (1954). The response of ear- phones in ears and couplers. The Journal of the Acoustical Society of
America, 26, 679.
Burkhard, M. D., and Sachs, R. M. (1975). Anthropometric mani-
kin for acoustic research. The Journal of the Acoustical Society of America, 58, 214.
Written by:
Wade R. Bray wbray@headacoustics.com HEAD acoustics, Inc., Brighton, MI
Mead C. Killion abonso@aol.com MCK Audio, Inc., Elk Grove Village, IL
Klaus Genuit Klaus.Genuit@head-acoustics.com HEAD acoustics GmbH, Herzogenrath, Germany
78 Acoustics Today • Spring 2022