Harvey Fletcher was born on September 11, 1884, in Provo, Utah, where he also died on July 23, 1981. He was a physicist, engineer, and educator who is recognized for his contributions to acoustics, electrical engineering, speech, medicine, music, sound pictures, and atomic physics.
Fletcher received his bachelor’s degree in 1907 from Brigham Young University. In 1911, he earned his PhD at the University of Chicago. Through his dissertation project on the measurement of the charge of an electron, Fletcher was involved in the development of the oil drop experiment, though this was later solely attributed to his adviser, Robert Millikan. After finishing his doctorate, Fletcher returned to Brigham Young University, where he was appointed chair of the physics department. He carried out his research and teaching there until 1916, when he began to work at the research and development department of Western Electric. In 1933, he joined the Bell Telephone Laboratories and became interested in acoustics and the physics of sound. From 1949, Fletcher worked at Columbia University, where he became professor of electrical engineering and established a department of acoustical engineering. From 1952 until his retirement in 1958, he was director of research at Brigham Young University and the first dean of BYU’s new College of Physical Engineering Sciences. Fletcher was appointed the first president of the Acoustical Society of America in 1929 and the president of the American Physical Society in 1945.
Fletcher’s research led to the development of one of the first electronic hearing aids and the invention of Western Electric’s 2-A Audiometer. For his research in electrical sound recording, which enabled the first successful stereophonic recordings and the first live stereo sound transmission, he is known as the “father of stereophonic sound.” Also well known are Fletcher’s contributions to the theory of speech perception, concepts of equal-loudness contours (Fletcher-Munson curves), and the “critical band” in audition.
- Fletcher, Harvey. “The Relative Difficulty of Interpreting the Spoken Sounds of English.” Physical Review 15, no. 6 (1920): 513–576.
- Fletcher, Harvey. “The Nature of Speech and Its Interpretation.” Journal of the Franklin Institute 193, no. 6 (1922): 729–747.
- Fletcher, Harvey, and Robert L. Wegel. "The Frequency—Sensitivity of Normal Ears." Physical review 19, no. 6 (1922): 553-565.
- Fletcher, Harvey. “Physical Measurements of Audition and Their Bearing on the Theory of Hearing.” Journal of the Franklin Institute 196, no. 3 (1923): 289–326.
- Fletcher, Harvey. "The Physical Criterion for Determining the Pitch of a Musical Tone." Physical Review 23, no. 3 (1924): 427-437.
- Fletcher, Harvey. Speech and Hearing. New York: Van Nostrand Co., 1928.
- Fletcher, Harvey, and J. C. Steinberg. "Articulation testing methods." Bell System Technical Journal 8, no. 4 (1929): 806-854.
- Fletcher, Harvey. "A space-time pattern theory of hearing." The Journal of the Acoustical Society of America 1, no. 311 (1930): 311-343.
- Fletcher, Harvey, and W.A. Munson. „Loudness, its Definition, Measurement and Calculation.” The Journal of the Acoustical Society of America 5, no. 2 (1933): 82-108.
- Fletcher, Harvey. "Auditory Patterns." Reviews of Modern Physics 12, no. 1 (1940): 47-66.
- Fletcher, Harvey. Speech and Hearing in Communication. New York: Van Nostrand Co., 1953.
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