ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

4aPP5. Fletcher and pitch.

John R. Pierce

Dept. of Music, Stanford Univ., Stanford, CA 94305

Preparing remarks on Fletcher's work on pitch changed drastically. My view of the development of our present understanding. In 1940 Jan Schouten showed that canceling out of the fundamental of a pitched tone did not change pitch. Schouten called the surviving pitch residue pitch. This inspired a spate of papers by people ignorant of earlier work. I had known Fletcher [Phys. Rev. 23(3), 427--437 (1924)] had shown that filtering out the fundamental and lower harmonics of a variety of musical sounds did not change the pitch, and, through synthetic sounds, that mere equal frequency spacing of tones did not give a pitch equal to the spacing. Thus, the pitch heard was evoked by harmonic partials. Unhappily, Fletcher proposed an unsound explanation in terms of production of the fundamental in the ear by nonlinearities. In a latter report, Fletcher [ 311--343 (1930)] gave an incomplete analysis of the functioning of the cochlea. Among his valid conclusions he said ``the pitch of a tone is determined both by the position of its maximum stimulation on the basilar membrane and also by the time pattern sent to the brain. The former is probably more important for high tones and the latter for low tones.'' That is our present understanding. Fletcher [ 637--645 (1951)] subsequently gave a ``correct'' analysis of the functions of the cochlea, agreeing with the experimental work of von Bekesy, and going a little beyond papers a year earlier by Peterson and Bogert and by Zwislocki.