Page 46 - Fall2013

Passings
Allan D. Pierce
Acoustical Society of America Publications Office West Barnstable, MA 02668
Kenneth N. Stevens
1924–2013
Kenneth N. Stevens, a Fellow, a former
President, Silver and Gold Medal awardee
of the Acoustical Society, and recipient of
the National Medal of Science, died Aug. 19
in Clackamas, Ore., at the age of 89. He was
a delightful companion, a kind and
thoughtful colleague, and a supportive
mentor to many that spent time in his labo-
ratory, including several research staff,
more than 60 graduate students, a good
number of undergraduates and many post-
doctoral students and visiting scientists. As
noted in his Gold Medal citation, one of
Ken’s closest associates and dear friend,
Dennis Klatt, once wrote that Ken was
“known for his devotion to students and his
miraculous ability to run a busy laboratory
while appearing to manage by a principle of
benevolent anarchy.” Whether you call it
benevolent anarchy or controlled chaos, Ken consistently cre- ated the optimal conditions for creativity and discovery.
His pioneering work at the intersection of engineering, physics, and linguistics was fundamental to many emerging fields in acoustics, and is cited across a number of Acoustical Society technical areas, such as Speech Communication, Psychological and Physiological Acoustics, Noise, and Signal Processing in Acoustics. Much of the early work in speech synthesis and lexical access for speech recognition came out of his laboratory through collaborations with Dennis Klatt and Victor Zue, among others. Other notable collaborations included seminal work with Arthur House on acoustic theo- ry, with Steven Green on audiometry, and with Amar Bose on network theory. His final work was the monumental “Acoustic Phonetics”, which was published in 1999, when he was 76. He was an author on 43 technical articles, 76 meet- ing abstracts and 2 patents published in the Journal of the Acoustical Society of America. He was also a fellow of IEEE.
Kenneth Stevens was born on March 23, 1924, to parents who emigrated from England. He originally intended to be a physician but fell in love with mathematics and the applica- tion of physics to real world problems. Ineligible for military
service due to the loss of an eye to cancer at age 4, he was able to continue with his edu- cation during World War II, receiving bachelor’s and master’s degrees in engineer- ing physics concurrently in 1945 from the University of Toronto while living at home as a student commuter. These were tense years for the Stevens family as his brother Pete was serving with the military and many relatives were at risk in England. He remained at the University for three more years to teach returning soldiers under the Canadian equivalent of the G.I. Bill, includ- ing his older brother, Pete. In 1948, Stevens came to MIT as a doctoral student in elec- trical engineering. His arrival coincided with the need of Leo Beranek for a teaching fellow in his course on acoustics and the presence in Cambridge of major pioneering
figures in the field of acoustic phonetics—that is, the acoustics of speech sound production and perception. Among these were Gunnar Fant, Roman Jacobson and Morris Halle. Seminal contributions from these early collab- orations include “An electrical analog of the vocal tract” (Stevens, Kasowski & Fant, 1953, JASA 25) and “Analysis by Synthesis” (Halle & Stevens, 1959, PSSCP 2). Ken was also one of the early researchers in the field of speech synthesis, as a member of the team developing DAVO (Dynamic Analog of the Vocal Tract). Dennis Klatt, Ken’s longtime colleague and friend, expanded this work as a member of the Ken’s Speech Communication Laboratory, ultimately developing the highly influential DECTalk. Other long-time laboratory collaborators include Stefanie Shattuck-Hufnagel and Joseph Perkell. Ken also produced one of the first x-ray movies of speech production. Thanks to the work of Kevin Munhall, Eric Vatikiotis-Bateson and Yoh'ichi Tohkura, these movies are available to the public and can be viewed on several web- sites, including YouTube.
His conversations with Jacobson and Halle also launched his lifelong fascination with the way languages organize acoustics and articulation to form the sounds of a language.
Acoustics Today accepts contributions for “Passings.” Submissions of about 250 words that may be edited in MSWord or plain text files should be e-mailed to AcousticsToday@aip.org. Photographs may be informal, but must be at least 300 dpi. Please send the text and photographs in separate files.
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