Effect of the Orientation of the Speaker's Head and Azimuth of a Noise Source on the Speech Reception Threshold for Sentences

摘要

The speech reception threshold (SRT) for sentences in a free field condition was investigated as a funcion of (1) the orientation of the speaker's head, and (2) the azimuth of a noise source, with the listener always looking in the direction of the speaker. A miniature electric microphone with a flat frequency response was glued to the upper lip of a pseudospeaker standing 2 m from a loudspeaker. For each of ten directional orientations of the pseudospeaker, corresponding to angles, of zero deg, 22.5 deg, 45 deg, 90 deg, and 180 deg relative to the loudspeaker, a list of 13 sentences was reproduced and rerecorded through the microphone. Results show that (1) the maximum effect of direction in speech radiation from the mouth of the speaker is, in terms of signal to noise ratio, 6 dB, and (2) the maximum effect of the azimuth of the noise source is 10 dB.