The 过程 of producing an 增 in the 能量 of a 声波 or an 為耳/音频 信号 This may be accomplished by 中项 of an 电子 扩器 or by 中项 of an acoustic resonator such as the 声波 box of a 樂/乐 乐器 an ear-trumpet etc Attaching i e coupling a 颤 对象 to another 表面 such as a soundboard wall or floor will result in a more efficient 转移 of 能量 and hence this 过程 may also be termed 扩 扩 or 增益 may be 测量 in dB/分贝 源 Barry Truax - Handbook for Acoustic 生态学 CD-ROM Edition Cambridge Street 出版 1999 - CSR-CDR 9901