48 channel beamforming microphone array for various measurement scenarios
This star array is a 48 channel measurement system designed for outdoor applications. The lightweight aluminum array body is designed as slim as possible to ensure easy handling and accurate microphone positioning. The included high-end tripod allows set-up in almost any measurement environment imaginable.
This array is foldable and connects to the data recorder.
Depending on a signal’s spectral composition, the recommended measurement distance varies between seven and 500 meters. Longer ranges are possible with consideration of wind and other influences. The wiring of the microphones is enclosed in and protected by the array body, guaranteeing the best possible acoustic transparency to measure accurate sound levels.
The array is foldable and fits in a mid-size station wagon. This array design represents a compromise between portability, map dynamic, and spatial resolution. Additionally, the array pattern is easy to identify and indicates wrong focus settings while still pointing to the source’s position. As this microphone array has 23 dB backfield suppression by design, it can be used in most outdoor applications.
The built-in studio microphones have an extremely linear frequency response. All are carefully hand-selected and calibrated to ensure stable sound pressure levels (+/- 0.5 dB). To allow long distances, the array is connected to the data recorder via two differential SymBus microphone connector cables (max. 20 m). The array comes with an integrated fixed focus Ethernet camera, delivered in different sensor sizes, resolutions and frame rates. Array and tripod are supplied in transport bags.
Technical Data
Array body diameter
3.4 m
Weight
7.4 kg
Video camera
Baumer VCXG-25C
Resolution
1920 x 1080 (Full HD)
Microphones
Electret condenser capsule
+ special designed preamplifier
Dynamic range
(Distance to the source: 7 m;
calculation points: 90.000)
7 dB – 9 dB, up to 50 dB with
advanced algorithms
Ingress protection code
IP20
Cable length to data recorder
up to 20 m (on request: 50 m)
Operating environment
-15 °C – 45 °C, up to 80 % RH
Videos
ACOUSTIC CAMERA Measuring Elephant Vocalizations in Nepal
Elephants produce infrasound to communicate with each other. The Acoustic Camera was used to investigate how the animals use sounds and perceive vocalizations for communication. In cooperation with the „Mammal Communication Lab“ of the University of Vienna, acoustic measurements were conducted in the Tiger Tops Elephant Camp of the Chitwan Nationalpark in Nepal. The scientists around Angela Stöger-Horwarth and Veronika Beeck are studying animal sound production and use the Acoustic Camera to visualize the sound of elephants communication in wildlife. The Acoustic Camera is used to better understand the language of the elephants: With our technology, the low-frequency sound generated by the animals can be visualized.
ACOUSTIC CAMERA: Pass By Measurement of an ICE train
In this measurement example, a fast-moving ICE train was measured. When moving objects are measured, the sound sources are located at different locations of the acoustic map in each instant of time. Besides, the so-called Doppler effect changes the spectrum and temporal progression of the amplitude of the emitted signal at the receiver. Therefore, common beamforming methods lead to diffuse acoustic maps. The PassBy module of NoiseImage was specially developed for moving measurement objects. It considers the movement and eliminates the Doppler effect. By using this software module, exact acoustic maps can be calculated even with fast-moving objects!
