本文為法國頻譜音樂作曲家格理賽之重要理論著作“La musique : le devenir des sons”（〈音樂：聲音的變化生成〉）之中譯。該文是了解格理賽音樂創作概念、音樂思想，以及法國頻譜音樂之重要文獻。格理賽於文中提出三個形容詞來說明其音樂作品之特色：差異的(Différentielle)、閾限的(Liminale)、過渡的(Transitoire)。「差異的」代表頻譜音樂企圖融入所有聲音現象，將差異作為組織音樂張力的基礎，並避免調性音樂的階級性和序列音樂的平等性。「閾限的」代表頻譜音樂將聽覺感知納入考量，活用感知閾限的特性。「過渡的」說明頻譜音樂重視聲響現象之動力本質，並將此特質作為構思音樂形式的基礎。由這三個形容詞也可看出二十世紀七零年代起，新生代法國「頻譜音樂」作曲家對以參數、組合、多核心、非連續性為特色之序列音樂的反動。

This is the Chinese translation of the French composer Gérard Grisey’s theoretical writing, La musique : le devenir des sons (Music, the becoming of sounds), an important document for understating the essential concepts in Grisey’s music as well as of spectralism generally. Grisey proposed three adjectives to describe his musical works : differential, liminal, and transitory:
• Differential, as this music intends to integrate all acoustic phenomenon and use differences to organize musical tension. In this way, spectral music also avoids the hierarchical structure of tonal music and the egalitarianism of the 12-tone technique and serialism.
• Liminal, as this music takes auditory perception into consideration, and plays with perceptive thresholds.
• Transitory, as this music considers sounds as a force field (“champ de force”), as a dynamic being. Moreover, the dynamic nature of sound is radicalized to become the very nature of musical form.