Abstract: Existing studies on metamaterials for acoustic radiation enhancement have predominantly focused on metamaterial design with ideal-source assumption, neglecting the coupling effect between electroacoustic transducers (as acoustic sources) and artificial structures. Considering the coupled system consisting of a dynamic loudspeaker and a Fabry-Perot (FP) resonant cavity, this paper develops its lumped-element theoretical model and, combined with finite-element simulations, investigates into the coupling-induced modifications in the response of the system. The results show that, when the FP resonance frequency is distinctly away from that of the loudspeaker, the electrical properties and vibrational state of the system remain almost unchanged even the radiation impedance is strongly altered by the FP resonance as compared to the loudspeaker standalone. Conversely, the FP resonance in the vicinity of the loudspeaker resonance causes nontrivial variations in the electromechanical response of the loudspeaker. The findings reveal the interaction between acoustic sources and resonant structures, which provides a theoretical reference for research on metamaterials for acoustic radiation enhancement.