| Popis: |
Direct measurements of the LDI index were performed by a new digital apparatus [G. B. Cannelli and S. Santoboni, Italian Patent No. 48694 A/87 and International Patent in progress] on a group of sounds having different impulsivity and recorded in the environment. The measurements showed that the LDI index accounts for fast fluctuations of sound level better than other noise indexes can do. In addition, the results indicated that the time constant is a critical parameter in measuring the impulse component of a sound. The sound recordings were presented in the laboratory at different sound levels and in balanced order to a group of naive subjects. They were asked to rate annoyance and impulsivity of each sound stimulus using a ten‐point numerical scale [G. Brambilla, M. R. Carretti, and S. Santoboni, Proc. Noise 88, Vol. 3, p. 159, Stockholm (1988)]. Correlation between the LDI values and the subjective ratings is in progress in order to test the validity of this index in the evaluation of both impulsivity ... |
