Acoustic vs electric power response of a high-performance MEMS microspeaker

This paper presents the characterization of the acoustic performance of an electrodynamic MEMS microspeaker and the influence of magnets position, which allows halving device size while intensifying the force factor. This work is based on the previously reported MEMS microspeaker dedicated to handheld electronics. A vacuum-formed seal has been designed and applied to enhance acoustic performance at low frequencies. The efficiency of the electroacoustic conversion is increased by a factor 5–10 compared to conventional microspeakers and low harmonic distortions were observed. Measurements of the acoustic power versus electrical input power were carried out in an anechoic room within the hearing range.