The InfraCyrus infrasound sensor

Infrasound sensors are used for a wide range of geophysical applications as the monitoring of volcanic
eruptions, the detection of bolides and the recording of infrasounds generated by earthquakes. In 2006 we
started the development of cheap infrasound sensors, based on commercial electret microphones. They have
been characterized by comparing their response function with existing broadband infrasound sensors. These
sensors, called InfraCyrus, have a good response between 1 and 10 Hz, making their application useful for
various geophysical purposes. Currently, about a dozen of sensors are deployed in the Neapolitan area
showing good performances in the recording of local and regional infrasonic transients.

INGV (Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Napoli - Osservatorio Vesuviano)

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