A novel dual-coil microspeaker design for enhanced low-frequency sound pressure level in tablets

This study proposes a novel nested dual-coil structure to address the challenge of delivering powerful low-frequency outputs from microspeakers under the strict thickness constraints of modern smart devices. The design was validated through electromagnetic–mechanical–acoustic coupled analyses and experimental measurements of the fabricated samples. Compared to a conventional single-coil structure, the proposed design improves the force factor by 34.13%, resulting in a 3.03 dB increase in the sound pressure level in the 100–500 Hz band, with a 0.63 dB trade-off in the 2–10 k Hz band. These results demonstrate the effectiveness of the design for improving bass performance under strict thickness constraints.