在梯田式環繞型音樂廳中，舞台區由觀眾四面環繞，舞台前緣線後之容積明顯增大，影響了樂手合奏所需要的聲場支持度。本研究因此試圖針對梯田式環繞型音樂廳，探討提升舞台聲場環境但不會減損觀眾聲場品質的可能性，研究中提出多種方案並以電腦模擬與1/20縮尺聲學模型實驗加以驗證，探討變因包括舞台側牆傾斜度、頂部反射板形式、頂部反射板高度等。
實驗結果發現，在早期舞台支持度(ST1) 與早期反射聲強度(GE-Ref)兩項聲學參數上，藉由調整側牆角度並裝設頂部反射板可獲致的改善幅度最高可達約2.5dB，其中前者由使用9.2米高平面反射板結合下傾側牆的方案得到，且其數值可達-15 B，而後者由等高度的1/4圓柱擴散反射板取得；以擴散反射板取代平面型反射板會造成早期舞台支持度降低約 1.0dB，但可微幅提升觀眾席整體聲強度。所有舞台支持度的改善皆會造成早期衰減時間(EDT)的降低，但都維持在可接受的範圍，而採用具50%開口率的陣列式反射板，可比另兩種實體反射板獲得相對較長的早期衰減時間。在9.2米高度使用擴散或陣列反射板，都是可以加強舞台支持度且能維持觀眾席聲能之可行方案，兩者並各自具有不同的附加優點。

In a terrace hall, the stage is surrounded by audiences’ seats from all sides. This change increases the volume behind the stage line and consequently influences the acoustical support desired for ensemble among musicians. This study is intended to improve the stage acoustics of a large vineyard hall while reducing harm to the audience area. Various schemes were proposed and verified using scale model measurements. Side stage wall tilting, overhead reflector type and overhead reflector height were studied.
Considering both the tilted angle of side stage walls and overhead reflector, early support (ST1) and early reflected strength (GE-Ref) can be improved the most by roughly 2.5 dB. The former was derived from the scheme with 9.2 m flat reflector with tilted side stage walls where ST1 reaches -15.0 dB. The latter was derived from the scheme with the same setting but with 1/4 cylinder diffusive reflector instead. Making the reflector surface diffusive caused roughly 1.0 dB drop in ST1 but slight increase in hall-average mid-frequency strength G. Early decay time became shorter but still acceptable when applying all of the improving strategies. The array reflector with 50 % of opening yielded longer early decay time than the other 2 types of solid ones at the same high level. Both the diffusive reflector and the array one hung at 9.2 m appeared to be safe solutions while each of them possessed different advantages on attributes other than support on stage.

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