Where 人类 beings are 听 to produce 声 then we will tend to impute 目的 to the 声音 事件 We will 听 it at some 级 as an Utterance In 特殊 whenever the 人类 voice is used as a 源 of 声波 in whatever 语义（上下文） the 概念 of Utterance will enter at some 级 into our 理解 of the 事件 This becomes 尤其 重要 in the 球体（范围） of 電聲學/电声学 樂/乐 projected in the 虚拟 空间 of 扬声器 where we can no longer rely on the 物理 and 社会 cues of the concert hall In 一般 non-music 声 产生 by individual creatures may be taken to indicate or express something about 内在 state reaction to 环境 events 响应/反应 to utterances by other creatures At whatever 级 the 感觉 of Utterance whether as indicator 信号 符号 sign or syntactic or semantic-syntactic 流 enters into our 感知 of the events 源 - Trevor Wishart 1985 On 声音 艺术 York Imagineering Press