Mapping Sound Pressure Levels: A Novel Approach to Determining Near-field and Far-field Regions

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Authors

  • Iliyan Yordanov ILIEV Department of Information Technology, Nikola Vaptsarov Naval Academy, Bulgaria
  • Hristo Zhivomirov KARAIVANOV Department of Theory of Electrical Engineering and Measurements, Technical University of Varna, Bulgaria

Abstract

The present study focuses on the spatial characteristics of the sound pressure level (SPL) generated by a circular piston (a circular-shaped acoustic transducer or loudspeaker). It presents a short theoretical review to aid in understanding the primary sound field characteristic – acoustic pressure – as a function of time, frequency, directivity angle, and distance from the source. The study introduces a simple and practical criterion for determining the near- and far-field boundary along the axis of the circular piston as a function of frequency. This criterion is validated through theoretical analysis and experimental measurements. Overall, the results show the influence of circular piston parameters on the SPL spatial distribution.

Keywords:

sound pressure level (SPL), spatial characteristics, near-field, far-field, boundaries, criterion

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