On the ability of consumer electronics microphones for environmental noise monitoring

Ghent University, Department of Information Technology (INTEC), Gent, Belgium.
Journal of Environmental Monitoring (Impact Factor: 2.18). 12/2010; 13(3):544-52. DOI: 10.1039/c0em00532k
Source: PubMed


The massive production of microphones for consumer electronics, and the shift from dedicated processing hardware to PC-based systems, opens the way to build affordable, extensive noise measurement networks. Applications include e.g. noise limit and urban soundscape monitoring, and validation of calculated noise maps. Microphones are the critical components of such a network. Therefore, in a first step, some basic characteristics of 8 microphones, distributed over a wide range of price classes, were measured in a standardized way in an anechoic chamber. In a next step, a thorough evaluation was made of the ability of these microphones to be used for environmental noise monitoring. This was done during a continuous, half-year lasting outdoor experiment, characterized by a wide variety of meteorological conditions. While some microphones failed during the course of this test, it was shown that it is possible to identify cheap microphones that highly correlate to the reference microphone during the full test period. When the deviations are expressed in total A-weighted (road traffic) noise levels, values of less than 1 dBA are obtained, in excess to the deviation amongst reference microphones themselves.

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    • "The introduction of cheap components that are easy to produce in large quantities has revolutionized the modern perception of monitoring systems. Sensors like MEMS (Micro- Electro-Mechanical-Systems) microphones are being transformed from low quality commercial products to class measurement-grade equipment and their integration into measuring devices has made possible the development of noise monitoring networks at costs that seemed impossible just a few years ago [1] [2] [3] [4] [5]. However the overall costs of implementing a properly functioning sensor grid includes installation, maintenance and quality control expenses which can easily prove much higher than the manufacturing cost of the network itself. "
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