On the Effect of Frequency and Amplitude Distortion on the Intelligibility of Speech in Noise

The effect upon the intelligibility of speech in noise of the interaction of sharp frequency limiting and severe peak clipping was studied. The results are compared with previously reported results of similar tests with frequency‐limited speech signals that were not subjected to amplitude distortion. The intelligibility of unclipped speech, relative to that of the peak‐clipped signal under corresponding experimental conditions, is a function of the signal‐to‐noise (S/N) ratio under test and is, to a rough approximation, independent of the frequency range of the speech signal passed. At high S/N ratios, the intelligibility of the unclipped speech signal is higher than that of the severely peak‐clipped signal. Under low S/N ratios, however, the intelligibility of the latter is considerably higher than that of the unclipped signal.