混响 is a result of 多 反射 A 声波 波 in an enclosed or semi-enclosed 环境 will be broken up as it is bounced back and forth among the 反射 表面 混响 is in 效果（效应） a multiplicity of 回声 whose 速度 of 重复 is too quick for them to be 感知（认为） as separate from one another W C Sabine 确定（建立） the official period of 混响 as the 时间 required by a 声波 in a 空间 to 减 to one-millionth of its 原始/原创 强度/ i e for its 强度 级 to change by -60 dB However 最小 the 混响 品质 of any 空间 whether enclosed or 不 helps to 定义 the way in which it is 感知（认为） Although it may 不 be realised 知觉 混响 is one of many cues used by a 听众 for orientation in a 特定 空间 The 比 of 直 to 混响 声波 is also an 重要 cue for the 感知 of 深 and 距 混响 will also 增 the 周围 噪 级 and apparent 响度 of 声 within a 空间 an 重要 因素 to consider in acoustic 设计

人工 混响 is 传统 产生 by 中项 of a 混响 室 or 回声 室 多 磁带 回声 or more commonly by exciting a metal spring or plate at one end and picking up the 延迟 信号 at another point However 数字 处理 设备 and 算機/计算机 技术 have been 发展 in recent years that allow a good 模拟 of naturally 产生 混响 These 系统 allow for a variable 比 of 直 to 反射 声波 and some include both global 混响 i e 反射 声波 from all directions and local 混响 i e that coming from the 方向 of the 声波 源 源 Barry Truax - Handbook for Acoustic 生态学 CD-ROM Edition Cambridge Street 出版 1999 - CSR-CDR 9901