Abstract: To research the acoustic characteristics of Helmholtz sound source （HSS）， a HSS combined a loudspeaker with a HR was designed and fabricated.With the changes of signal frequencies， the response characteristics of HSS， including equivalent acoustic impedances， terminal voltages， output sound pressures and electro-acoustic efficiencies， were preliminarily explored through numerical simulations and experiments.Results show that the acoustic characteristics of HSS are related to the interactions between loudspeaker and HR， and the equivalent acoustic impedance characteristics of HSS are dominated by HR.The resonances of both loudspeaker and HR may strengthen sound radiation and thus improve electro-acoustic efficiency of HSS.Under selected experimental conditions， the maximum output sound pressure of HSS may be 22 times of that generated by loudspeaker， thereby the electro-acoustic efficiency reaches up to 113%.

Key words: loudspeaker, Helmholtz resonator（HR）, resonance, sound pressure, electro-acoustic efficiency

摘要： 为研究Helmholtz声源的声学特性，设计并制作了一款由扬声器和Helmholtz共振器组成的Helmholtz声源，并对其等效声阻抗、两端电压、输出声压值和电声转换效率随信号频率变化的响应特性进行了初步探索。结果表明，Helmholtz声源的声学特性与扬声器和Helmholtz共振器的相互作用有关，Helmholtz声源的声学阻抗特性主要由Helmholtz共振器决定；扬声器的谐振或Helmholtz共振器的共振能够增强Helmholtz声源的声波辐射能力，可以有效提高声源的电声转换效果；在选定的实验条件下，Helmholtz声源的最大输出声压值约是扬声器的22倍，此时Helmholtz声源的电声转换效率高达113%。

关键词: 扬声器, Helmholtz共振器, 共振, 声压, 电声转换效率