比较 to 噪 which is 讨厌 声波 a 信号 is any 声波 or 信息 which is 意味 to be 听 to 测量 or 储存

In 声景观（声景） 研究 声波 信号 are always treated in 关系 to their 周围 or 基调 语义（上下文） since they 补充 that 语义（上下文） in the same way figure and ground are 相关 in 视觉 感知 Thus a 研究 of 信号 also 揭露 重要 信息 about the 整体 声波 环境

声波 信号 may be 研究 in any of the 跟随 ways
on the 基础 of their acoustic 特征 which may represent a 识别 代码 or other 模式 关于（附属） to their 用 主观 by their 个别 感知（认为） meanings 历史 according to their 演变 within a 特定 社会 语义（上下文） 比较 by 种类 and 功能（函数） in different cultures or 周期（时期） symbolically according to their 内涵 and 联合 meanings

声波 信号 are 重要 in the way in which they regulate the life of a 团体 and reflect its character Those of 历史性 importance may be termed 声标 The area over which a 声波 信号 may be 听 is its profile or acoustic 空间 which may be regarded as its 球体（范围） of influence In 现代 都市 环境 many 团体 信号 are 消失 both 物理 and 声学（听觉） with rising 周围 噪 级

源 adapted and summarised from Barry Truax - Handbook for Acoustic 生态学 CD-ROM Edition Cambridge Street 出版 1999 - CSR-CDR 9901