语音质量是基于对语音的主观评价。可以基于偏好、响度、可懂度和原始说话人声音、传输信道和/或在人工语音的情况下，语音合成器特性的可识别性来评估语音。负责编写语音质量测量工程实践的IEEE主观测量小组委员会得出结论，现在不应推荐单一方法。 目前的推荐做法仅涉及偏好测量，将暂时概述三种方法。这些是参考法、相对偏好法和类别判断法。

Speech quality is based on the subjective appraisal of speech. Speech may be appraised on the basis of preference, loudness, intelligibility, and recognizability of properties of the original speaker's voice, of the transmission channel, and/or in the case of artificial speech, of the speech synthesizer. The IEEE Subcommittee on Subjective Measurements, charged with writing an engineering practice for the measurement of speech quality, has concluded that a single method should not now be recommended. The present Recommended Practice is concerned only with preference measurements for which three methods will be tentatively outlined. These are the Isopreference Method, the Relative Preference Method, and the Category-Judgment Method.