Broadband MEMS Speaker by Single-Way Multi-Resonance Array with Acoustic Damping Tuning: A Proof of Concept

This paper proposes a resonance synthesis (RS) method for broadband MEMS speaker. It involves multi-resonance actuator array with proper acoustic damping tuning. A broadband design for MEMS speaker is demonstrated based on the RS method and validated by simulation. Compared with state of the art methods, the proposed design achieves a much wider -3 dB SPL bandwidth from 2 kHz to 10 kHz, which is an improvement in bandwidth of ~250%. A proof of concept experiment is conducted by two piezoelectric MEMS speakers with different resonant frequencies of 3.6 kHz and 6 kHz. The experimental results agree with simulation. The RS method combines multiple mechanical resonances, forms highly sensitive and flat acoustic output, and yet only takes a single-way electrical signal as input.