A 设备 used to 影响 certain parts of the 频谱 of a 声音 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 滤波器 are

- 高通 滤波器 which 衰减 低 频率 below the cut-off 频率
- 低通 滤波器 which 衰减 高 频率 above the cut-off 频率
- 带通 滤波器 which combine both 高通 and 低通 功能(函数)
- 带阻 滤波器 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 滤波器 which 通过 a 可控制 amount of the 频谱 in each 带/乐队
- shelving 滤波器 which 提升 or 衰减 all 频率 above or below the shelf point
- 共鸣 or 共振峰 滤波器 with variable 中心 频率 and Q值

The Q值 of a 滤波器 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 滤波器 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 滤波器 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 滤波器 may be 相互连接 to 形(曲)式 a 滤波器 bank 化约 from Barry Truax - Handbook for Acoustic 生态学 CD-ROM Edition Cambridge Street 出版 1999 - CSR-CDR 9901

With Comb-Filtering a 声音 is passed through a group of 滤波器 通常 分布 equidistantly The 模式 of 声音 处理 changes the 频谱 content of 声音 around the selected 频率 possibly 增强 them to the extent of 生成 共鸣 when the width of the 过滤 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 电子声学 音乐 PhD Thesis University of East Anglia

滤波器 have also been used as 音乐 'instruments' in 现场演出 表演 most significantly in a 数 of 作品 by Karlheinz Stockhausen 包括 Mikrophonie I 1964 Prozession 1967 and Kurzwellen 1968 The 滤波器 were used to 变形 the 声音 of a large tam-tam picked up by 话筒(麦克风) moved by 表演者 over the 表面 In the latter two 作品 the 滤波器 were also applied to the 声音 from a contact 话筒(麦克风) attached to a viola 源 - Richard Dobson 1992 A 词典 of 电子 and 计算机 音乐 技术 牛津 University Press