A 设备 used to 影响 certain parts of the 频谱 of a 声波 by causing the 衰减 of certain 频率 频带 while allowing other 频带 to 通过 非衰减 Some common 种类 of 滤器 are

- 高通 滤器 which 衰减 低 频率 below the cut-off 频率
- 低通 滤器 which 衰减 高 频率 above the cut-off 频率
- 带通 滤器 which combine both 高通 and 低通 功能(函数)
- 带阻 滤器 which 表演 the opposite 功能(函数) of the 带通 种类
- 倍频程(八度) half-octave third-octave tenth-octave 滤器 which 通过 a 可控 amount of the 频谱 in each 带/乐队
- shelving 滤器 which 提升 or 衰减 all 频率 above or below the shelf point
- 共鸣 or 共振峰 滤器 with variable 中心 频率 and Q值

The Q值 of a 滤器 is a measure of its 共鸣 and is 定义 as the 比 of 中心 频率 to the 频带宽度(带宽) The narrower the 频带宽度(带宽) the 较高 the Q值 and the more the 滤器 will 'ring' or go into 振荡 when stimulated by a 信号 with 能量 near the 中心 频率 A 持续 Q值 滤器 varies its 频带宽度(带宽) as a 功能(函数) of the 中心 频率 always keeping the 比 between them the same

A group of such 滤器 may be 相互连接 to 形(曲)式 a 滤器 bank 化 from Barry Truax - Handbook for Acoustic 生态学 CD-ROM Edition Cambridge Street 出版 1999 - CSR-CDR 9901

With Comb-Filtering a 声波 is passed through a group of 滤器 通常 分布 equidistantly The 模式 of 声波 处理 changes the 频谱 content of 声 around the selected 频率 possibly 增强 them to the extent of 生成 共鸣 when the width of the 滤 areas become very 薄 正弦 频率 then start to oscillate in 响应/反应 to the 回授(反馈) 创作 in those 频率 源 - Rodolfo Caesar 1992 The 作曲 of 電聲學/电声学 樂/乐 PhD Thesis University of East Anglia

滤器 have also been used as 樂/乐 'instruments' in 现场 表演 most significantly in a 数 of 作品 by Karlheinz Stockhausen 包括 Mikrophonie I 1964 Prozession 1967 and Kurzwellen 1968 The 滤器 were used to 变形 the 声 of a large tam-tam picked up by 声筒(麦克风) moved by 表演者 over the 表面 In the latter two 作品 the 滤器 were also applied to the 声波 from a contact 声筒(麦克风) attached to a viola 源 - Richard Dobson 1992 A 字典 of 电子 and 算機/计算机 樂/乐 技术 牛津 University Press