Klippel has announced its program for the 11th International Symposium on Electroacoustic Technologies, taking place in Shenzhen on September 12-13. Engineer Christian Bellmann will deliver a research paper and, on the second day, lead an afternoon master class devoted to loudspeaker directivity measurement.
The paper, 'Acoustic Center Localization for Holographic Directivity Measurements of Loudspeakers,' examines how the expansion point used in spherical-wave models can be located more efficiently. It compares delay-based techniques with methods that optimize the center from spherical-harmonic coefficients, using both simulated data and measurements of real loudspeakers.
The master class moves from conventional anechoic turntable measurements to modern near-field holography. Its agenda includes double-layer scanning, spherical-wave decomposition, and holographic post-processing, showing how near-field data captured outside an anechoic chamber can be reconstructed as free-field radiation.
Bellmann will also cover the extraction and interpretation of spatial transfer functions, on-axis response, sound power, and directivity. The program connects those measurements to room interaction and to 3D-audio applications such as beam steering, giving the session a broader scope than a survey of measurement hardware.
The underlying engineering problem is a practical one: high-resolution directivity data must be balanced against measurement time, room conditions, and computational complexity. The ISEAT sessions address that trade-off directly, with an emphasis on methods that can shorten development work without weakening the result.