Some Features of Physical Structure of Acoustic Fields of Stereophonic Systems

The definition of an ideal stereophonic system is given and a theoretical example of such a system is presented; this system restores exactly, at all the points of the secondary field, the physical structure of the primary field according to all the acoustic parameters. A multichannel system is usually considered as a practical compromise. The definition of a real stereophonic system is given; such a systems's basic requirement is the reconstruction of localization effect, which is best obtained in the primary free field. Since the sound oscillations are longitudinal, the movements of air particles are rectilinear in the direction from each actual sound source to each point of the primary field. The conditions of restoration of rectilinearity of oscillations of air particles in the secondary field are considered and the basic equation of stereophony is deduced. It has been proved that in a general case the multichannel system cannot restore, in the secondary field, the rectilinear oscillations of air particles but transforms them into elliptical ones. It has also been proved that the principal cause of the physical character which makes it impossible to obtain the undistorted localization effect in a general case in all points of the secondary field, is an insufficient velocity of sound in the air. Recommendations are given, taking into consideration the use of the established regularities in such a way as to create a practical possibility of obtaining an excellent and good stereophonic effect in the whole area of the theater.

Print ISSN

0361-4573

Published

1967-02

Content type

Original Research

DOI

10.5594/J09186