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Updated: May 9, 2026

The Measurement of Unsteady Surface Pressure Using a Remote Microphone Probe
Published on: December 3, 2016
Evaluation of moving-coil loudspeaker and passive radiator parameters using normal-incidence sound transmission
Timothy W Leishman1, Brian E Anderson
1Acoustics Research Group, Department of Physics and Astronomy, Brigham Young University, N283 Eyring Science Center, Provo, Utah 84602, USA. tim_leishman@byu.edu
Abstract:
The parameters of moving-coil loudspeaker drivers are typically determined using direct electrical excitation and measurement. However, as electro-mechano-acoustical devices, their parameters should also follow from suitable mechanical or acoustical evaluations. This paper presents the theory of an acoustical method of excitation and measurement using normal-incidence sound transmission through a baffled driver as a plane-wave tube partition. Analogous circuits enable key parameters to be extracted from measurement results in terms of open and closed-circuit driver conditions. Associated tools are presented that facilitate adjacent field decompositions and derivations of sound transmission coefficients (in terms of driver parameters) directly from the circuits. The paper also clarifies the impact of nonanechoic receiving tube terminations and the specific benefits of downstream field decompositions.
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