| Abstrakt: |
Both loudness and annoyance depend-under some conditions-on duration, but in opposite ways. Some data suggest that the loudness of a continuous sound decreases over time, after the first second or so. Data and common observation suggest that the annoyance of a continuous sound increases over time. To catch these changing responses on the wing, we have applied a method of successive magnitude estimation. An observer hears a continuous sound to which he assigns a number whenever a 2-s light appears. He is instructed to match a number either to the sound's loudness or to its annoyance. Results show that at low levels, as duration lengthens loudness decreases, more so for high-frequency tones, less so for low-frequency tones and wide-band noise. At higher levels, loudness remains constant as a function of duration. On the other hand, annoyance grows markedly with duration-especially during the first 15 s-but its rate of growth and magnitude seem to depend on level, spectral characteristics, fluctuations, and so forth. Successive magnitude estimation provides the data needed to sort out these interactions and so should lead to usable rules about the relation between annoyance and sound duration. [ABSTRACT FROM AUTHOR] |
