Contribution

MEMS-Microphone Arrays for the Measurement of Spatial Loudspeaker Characteristics in the Near-Field

Authors

* Presenting author
Day / Time: 20.03.2025, 11:00-11:40
Room: Hall E, Poster Island E
Typ: Poster
Session: Acoustic Measurements and Sensor Technology (Poster Island E)
Information: The posters will be exhibited in Hall E north from Tuesday to Thursday, sorted by thematic context in the poster island indicated in the session title. The poster session at the specified time offers the opportunity to enter into discussion with the authors.
Abstract: In this article we show the design and application of microphone arrays comprising a high number of MEMS microphones. The microphone arrays consist of up to 32 digital MEMS microphones, which are mounted directly on PCBs that contain additional electronics for the conversion of PDM to PCM signals. Furthermore the PCB contains a USB-audio interface, which allows the usage with a computer without special drivers.Such arrays can be used in various test scenarios where depending on the application different post-processing algorithms can be applied to compute the radiation pattern for the far-field.We will present two possible applications. The first is the measurement of the 3D directional characteristic of a loudspeaker. For this, a circular array with 32 microphones is mechanically moved in the near-field of the loudspeaker, so that an enveloping surface is covered by the microphones to fully capture the radiated sound.Another application uses a linear array with 16 microphones which is mounted stationary in the near-field in front of an active line-array speaker. With this setup, it is possible to capture the frontal vertical directional characteristics of the loudspeaker in real-time which can be seen as an inverse acoustic camera.