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本文應用多孔介質 (porous medium) 二維有限頻域分析 (Finite Element Frequency Domain Analysis，FEFDA)計算聆聽室的頻率響應 (Frequency Respones)。文中分析驗證吸音泡棉 (Acoustic Foams)的吸音係數(Sound Absorption Coefficient)與施羅德擴散器 (Schroeder Diffuser)的極響應(Polar Responses) 及擴散係數 (Diffusion Coefficient)，並探討結合吸音泡棉與施羅德擴散器於聆聽室 (Listening Room) 空間聲場頻率響應的影響。 研究中首先應用有限元素頻域分析與雙麥克風法 (Two-Microphone Method) 計算吸音泡棉的吸音係數，並與一維理論解進行比較，完成準確性驗證。接著應用有限元素頻域分析繪製500 Hz施羅德擴散器的極響應圖(Polar plot)並驗證其擴散效果。從極響應圖中可觀察出七槽施羅德擴散器的擴散效果最佳，單槽有顯著的集中反射現象，擴散效果差。最後本文應用均佈脈衝聲壓與邊界條件模擬聆聽室的頻率響應，探討結合吸音泡棉與施羅德擴散器對聆聽室頻率響應的影響。結果顯示聆聽室附加三個施羅德擴散器較附加一個擴散器的擴散效果為佳。結合吸音泡棉與施羅德擴散器後，聆聽點各倍頻帶 (Octave Band)的位移振幅皆顯著下降，顯見吸音泡棉的吸音效果。惟擴散器與吸音泡棉的結合使用，須考量適切的聆聽頻率響應需求予以適當的設計。

The finite element frequency domain analysis (FEFDA) of the porous medium is used to calculate the frequency responses of a listening room in this study. Related information, such as sound absorption coefficient of acoustic foams, and polar responses and diffusion coefficient of Schroeder diffuser, are estimated and verified to figure out the effect in the frequency response of the sound field when installing the acoustic foams and Schroeder diffuser in the listening room. FEFDA and two-microphone method are applied to calculate the sound absorption coefficient that is further compared with one-dimension theory to assess the accuracy. A polar plot of 500 Hz Schroeder diffuser is prepared according to the FEFDA, and indicates a 7-slot diffuser performs better diffusion and a single-slot diffuser has bad performance due to obviously concentrated reflection. Finally, this study simulates the frequency response of the listening room based on the average distribution pulse acoustic pressure and boundary conditions to discuss the influence from the combination of the acoustic foams and Schroeder diffuser. The result shows that the better diffusion performance is incurred when applying three Schroeder diffusers with an extra diffuser. The acoustic foams has significant efficacy in adsorbing sounds proven by obviously decreasing of the displacement amplitude at each octave band. However, an appropriate frequency response should be taken into consideration while constructing the acoustic foams and Schroeder diffuser.