Denis Smalley has 介绍 this 术语 as a 手段(意味着) of 描述 the 电平/级别 or 度 to which listeners perceptually relate 声音 to real or imagined 物理 and gestural 源 within an 幻听 聆听 situation 代理 may 描述 the 识别 of 熟悉 instrumental or vocal 制作 when reproduced in 录制 形（曲）式 As the 度 of 代理 becomes more 遥控 listeners may ascribe imagined causes to 声音 and their spectromorphological 演变 or apprehend the 声音 as 'abstract' Smalley 术语 these 变化 电平/级别 as 'orders of surrogacy'