| Abstrakt: |
When a pair of short temporally spaced sound bursts are presented monaurally, and the listeners are requested to match the loudness of a third comparison burst to the total loudness of the pair, a fundamentally different result is obtained than when they are instructed to match the loudness of the comparison burst to that of the second burst in the pair. The most striking difference has been obtained thus far with the sound frequencies of the first two bursts at 1 and 4 kHz, respectively, and the frequency of the comparison tone at their geometric mean when the listeners judged the loudness of the burst pair and at 4 kHz when they judged the loudness of the second burst. In the first situation, the loudness level of the pair appeared increased by almost 10 dB over the loudness level of a single burst and was independent of the time interval between the bursts in the pair. In the second situation, the loudness was increased by only 3 dB for very short time intervals, and the increment decreased to zero within 80 msec. Since, at durations greater than 80 msec the tone bursts are heard as distinctly separate entities, we conclude that listeners consciously summate the loudness of the bursts when asked to judge the total loudness of the pair. [ABSTRACT FROM AUTHOR] |
