Phase sensitivity microphone calibration

Milhomem, T. A. B. Electroacoustic Laboratory, National Institute of Metrology, Quality and Technology, Duque de Caxias, RJ, Brazil, tbmilhomem@inmetro.gov.br

Soares, Z. M. D. Electroacoustic Laboratory, National Institute of Metrology, Quality and Technology, Duque de Caxias, RJ, Brazil, zmsoares}@inmetro.gov.br

Abstract

Measurement microphone calibration usually involves determine its modulus sensitivity as a function of frequency, however, in last years, demand for its phase sensitivity information has increased. In view of that, phase measurement was included in primary calibration of measurement microphones and international comparisons of that calibration have been performed. In order to allow the dissemination of the primary calibration to the end user, the secondary calibration of measurement microphones was investigated. This study comprises a phase measurement of a half-inch laboratory standard microphone and of a set preamplifier plus half-inch laboratory standard microphone by the comparison method.

Keywords:

calibration

microphone

phase sensitivity

pressure sound field

coupler

References

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