本文采用以谱距离为基础的LPC CD、Bark SD和Mel CD三种客观失真测度 ,对若干种语音编码设备及它们的级联系统进行了客观音质评价实验研究 .结果表明 ,这三种测度单独应用都具有较好主、客观相关性 ,它们的组合 ,给出更好的相关结果 .因此 ,可以推断 ,这些测度作为语音系统的音质评价是有一定有效性和实用性的 . In this paper, three kinds of objective distortion measures of LPC CD, Bark SD and Mel CD based on spectral distance are used to evaluate the objective sound quality of several speech coding devices and their cascaded systems. The results show that these three measures alone Applications have good main and objective relevance, and their combination gives better correlation results, so it can be concluded that these measures have certain validity and practicability as the sound quality evaluation of speech system.