AES Europe 2026

This work presents a measurement uncertainty evaluation of
the free-field sensitivity of a MEMS microphone using a
substitution comparison method. The measurement setup is
based on principles used in secondary microphone
calibration, with sensitivity determined relative to a
calibrated reference microphone. The uncertainty analysis
follows the Guide to the Expression of Uncertainty in
Measurement (GUM), where Type A; Type B uncertainty
evaluations are propagated through a defined measurement
model to obtain the final measurement result. The MEMS
microphone sensitivity is estimated together with an
expanded uncertainty, where the calibration uncertainty of
the reference microphone is identified as the dominant
contributor. Broadband results show that the measured
sensitivity is close to the typical manufacturer
sensitivity over a wide frequency range; follows a
similar frequency trend. The proposed approach enables
reproducible estimation of the free-field sensitivity of
MEMS microphones; provides a clear framework for
uncertainty evaluation.