Page 49 - Summer 2015

Table 1: ASA Psychoacoustician Award Winners and Presidents
Gold Medal
Silver Medal
Helmholtz-Rayleigh Interdisciplinary Silver W. Dixon Ward 1991 Jens P. Blauert 1999
William M.
Hartmann 2001
ASA Presidents
Harvey Fletcher 1957 Ira J. Hirsh 1992 David M. Green 1994 Brian C. J. Moore 2014
Lloyd A. Jeffress 1977 Eberhard Zwicker 1987 David M. Green 1990 Nathaniel I.
Durlach 1994 Neal F.
Viemeister 2001 Brian C. J. Moore 2002 H. Steven
Colburn 2004 William A. Yost 2006
Harvey C. Fletcher 1929 J. C. R. Licklider 1958 Ira J. Hirsh 1967 Karl D. Kryter 1972 David M. Green 1981 W. Dixon Ward 1988 William M.
Hartmann 2001 William A. Yost 2005 Judy R. Dubno 2014
Although a defining aspect of Fechner’s psychophysics was relating perception to physics, attempts to find the physical bases for perception predate Fechner by centuries. The early Greeks, such as Pythagoras, sought physical/mathematical explanations for many aspects of music. The Greeks did not have a name (e.g., psychoacoustics) for their studies, but they were engaged in psychoacoustics just as much as Fech- ner and others before and after him.
I divide the history of psychoacoustics into several peri- ods: Psychoacoustics Before the 19th Century, the Realm of Helmholtz, Bell Laboratories, the Theory of Signal De- tection, the Study of Complex Sound, and Auditory Scene Analysis (Yost, 2014; Table 1). I have relied on the classic perception history text by E. G. Boring (1942) and R. B. Lindsay’s article on the history of acoustics (1966).
Psychoacoustics Before
the 19th Century
As already mentioned, Pythagoras and fellow scholars were fascinated by music. Greek musical instruments were sim- ple-stringed (e.g., lyre), tubed (e.g., flute), and percussion (e.g., tympanum) instruments. Greek scholars tried to un- derstand the physical/mathematical bases of musical scales, consonance, and dissonance produced by these instruments.
Aristotle (around 350 BC) was the first to suggest that sound is carried by air movement. But Leonardo De Vinci (around 1500) was likely the first to realize that such movement was probably in the form of waves. Galileo Galilei, 100 years lat- er, scraped a chisel across a brass plate, producing a screechy pitch. Galileo calculated that the spacing of the grooves caused by the chisel was related to the perceived pitch of the screech. However, it wasn’t until the 17th century that the relationship between vibratory frequency and pitch was confirmed. Robert Hooke (1635-1703) made a wheel with small teeth sticking out from the edge at equal intervals. As the wheel rotated on an axle and the teeth pressed on a card,
a sound was produced when the card vibrated. The pitch of the sound rose as the wheel’s rotational speed increased. A century and a half later, Felix Savart (1791-1841) refined the wheel to study human hearing (Figure 2).3
Figure 2. An illustration of a Savart wheel. An earlier ver- sion was used by Hooke to study sound frequency and pitch.
By the 18th century, the main method for creat- ing sound for the study of pitch was the tuning fork, invented by John Shore in 1711. Shore (1662-1752) was an accomplished trum- peter and lutenist, and he is reported to have said at the beginning of a con- cert that he did not have a
pitch “pipe,” a common means to tune instruments, but he did possess a pitch “fork.” Other forms of resonators, sirens, tubes, and strings were used to study sound until the use of electrical devices and the vacuum tube (invented about 1910) came into existence.
The early scholars had their humorous observations as well. For example, Leonardo Da Vinci wrote “an average human looks without seeing, listens without hearing, touches with- out feeling, eats without tasting, moves without physical awareness, inhales without awareness of odor or fragrance, and talks without thinking.”
Realm of Helmholtz (1800s-Early 1900s)
Hermann von Helmholtz was a commanding, if not the lead- ing, scientist of the 19th century. His book (1863/1954) On the Sensations of Tone as a Physiological Basis for the Theory of Music was the major reference for hearing and musical
3 Wave-Action in Nature. (1873).The Popular Science Monthly, Volume III, 7–8.
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