Summary

Recommendation ITU-T P.806 describes a methodology for evaluating the subjective quality of speech samples using multiple rating scales. In addition to scores for overall quality and loudness, the methodology yields scores for six perceptual quality (PQ) attributes of the speech sample. Each of these PQ scores is based on ratings of the amount or degree of degradation present in the sample for an attribute that underlies listener's judgment of speech quality. Four of the PQ scores represent degradation associated with the speech signal and two of the PQ scores represent degradation associated with the background noise. The methodology is designed to be used with naive subjects and yields scores for overall quality and loudness plus scores for the six PQ attributes of the speech sample. These PQ scores can be used to provide diagnostic information on the underlying causes of speech quality degradation.

This Recommendation includes an electronic attachment containing audio samples for the conditions described in Appendix I.