From the inaugural event in 2007 to the 10th edition in 2025, the International Symposium on ElectroAcoustic Technologies (ISEAT) has continuously evolved with the times, expanding its scope and enriching its content while making increasingly significant contributions to the advancement of sound technology.

Experts and scholars from around the world, technology decision-makers, and senior engineers have gathered at ISEAT to experience the latest achievements in sound technology, gain insights into cutting-edge developments in electroacoustics, and engage in comprehensive exchanges across academia and industry.

At ISEAT, global expertise converges, ideas from diverse disciplines collide and inspire, sparking new perspectives and igniting the creativity that drives innovation and progress. Through this platform, academia and industry join forces to advance the remarkable journey of sound technology together.

The 11th International Symposium on ElectroAcoustic Technologies (ISEAT), themed “Immersive Sound: Technology + Art,” will be held on September 12–13, 2026, in Shenzhen, China.

At ISEAT, participants will have the opportunity to access the latest breakthroughs in acoustics and electroacoustic technologies without time barriers or language limitations, engage directly with leading experts, scholars, technology leaders, and senior engineers from around the world, exchange practical experiences face-to-face, and broaden their global perspectives.

ISEAT–Klippel Master Class

The ISEAT–Klippel  Master Classn  will be featured during the 11th International Symposium on ElectroAcoustic Technologies (ISEAT).

It will cover both conventional far-field directivity measurements and advanced near-field holographic measurement technologies, providing a systematic introduction to how free-field radiation characteristics can be reconstructed from near-field measurement data through spherical wave decomposition, double-layer scanning, and holographic post-processing techniques.

It will further explore methodologies for extracting and interpreting key acoustic parameters, including spatial transfer functions, on-axis response, sound power, and directivity characteristics. It will also discuss the critical role of these parameters in loudspeaker evaluation, room interaction analysis, and modern 3D audio applications such as beamforming.

It will closely integrate theoretical explanations with practical demonstrations, enabling participants not only to gain a solid understanding of fundamental principles but also to acquire hands-on experience with advanced acoustic measurement technologies.

1. Title

Loudspeaker Directivity Measurement

2. Time

September 13, 13:30 – 18:00 (4.5 hours total, including 15-minute breaks and a 15-minute Q&A session)

Open to all attendees of the 11th ISEAT

3. Language

AI-powered real-time interpretation (English to Chinese) will be provided by the symposium.

4. Speaker

Christian Bellmann

Senior Development Engineer Radiation & Vibration Testing, Klippel GmbH

Klippel GmbH

Christian Bellmann graduated in mechatronics from Dresden University of Technology in 2013. His master’s research focused on separating direct sound and room reflections using holographic methods to enable directivity measurements under non-anechoic conditions. He is a Senior R&D Engineer at Klippel GmbH, working on loudspeaker measurement systems with a focus on acoustic holography and sound and vibration testing.

5、Agenda

Klippel Master Class Agenda

a. Introduction and Motivation

Why loudspeaker directivity matters

Applications

b. Fundamentals of Acoustic Measurements

Near-field and far-field fundamentals

Measurement principles and instrumentation

c. Conventional Directivity Measurements

Anechoic turntable measurements

Accuracy, limitations, and best practices

d. Near-Field Holographic Measurements

Double-layer scanning and spherical wave decomposition

Free-field reconstruction in non-anechoic environments

e. Directivity Analysis

Spatial transfer function, sound power, and directivity

Interpretation for loudspeaker evaluation and beam steering

f. In-Situ Loudspeaker Measurements

Accurate acoustic measurements in any environment

Fundamental, distortion, and transient measurements

g. Summary and Discussion

Key takeaways and future perspectives

Questions and discussion

How to attend the 11th ISEAT?

Using a computer or mobile phone, access the registration system via the official conference website or the WeChat Official Account ("电声技术国际研讨会ISEAT", ID: ISEATorg), or scan the QR code below:

We look forward to meeting you in Shenzhen on September 12–13.