Audiometric Calibration: Air Conduction

Abstract

The main goal of this article is to discuss the calibration of air-conducted signals delivered by an audiometer via an earphone or a loudspeaker. The common types of earphones used in hearing testing are described and the importance of calibrating these transducers is discussed. After covering the instruments used for calibration, the performance parameters measured in the calibration process are examined. The limitations of our current methods are discussed and areas for improvement are considered.

Keywords

Air conduction - output level - pure tone audiometry - attenuator linearity - frequency accuracy

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