An effect of temporal asymmetry on loudness

Abstract

A set of experiments was conducted to examine the loudness of sounds with temporally asymmetric amplitude envelopes. Envelopes were generated with fast-attack/slow-decay characteristics to produce F-S (or "fast-slow") stimuli, while temporally reversed versions of these same envelopes produced corresponding S-F ("slow-fast") stimuli. For sinusoidal (330-6000 Hz) and broadband noise carriers, S-F stimuli were louder than F-S stimuli of equal energy. The magnitude of this effect was sensitive to stimulus order, with the largest differences between F-S and S-F loudness occurring after exposure to a preceding F-S stimulus. These results are not compatible with automatic gain control, power-spectrum models of loudness, or predictions obtained using the auditory image model [Patterson et al., J. Acoust. Soc. Am. 98, 1890-1894 (1995)]. Rather, they are comparable to phenomena of perceptual constancy, and may be related to the parsing of auditory input into direct and reverberant sound.

Comparison of loudness models for time-varying sounds

“…Stecker and Hafter [44] measured the loudness of bursts of tones with the same duration, butw ith either quickly rising and slowly falling level(damped stimuli)orvice versa (ramped stimuli). Fort one frequencies between 330 and 6000 Hz, theyf ound that loudness wasl arger for ramped than for damped stimuli, although spectrum, duration and intensity were the same.…”

“…This recencye ff ect could only be partly modeled with the auditory image model (AIM, [45]). Since AIM wasnot explicitly designed as aloudness model, loudness of the same stimuli as used by Stecker and Hafter [44] waspredicted with the twoloudness models under consideration in the present study to investigate if the models can account for such at emporal asymmetry in loudness perception. The lower panels of Figure 5 showt he predicted instantaneous (gray lines)a nd shortterm loudness (black lines)f or both models for ac arrier frequencyo f1 .5 kHz and ap eak levelo f8 0dBS PL for Figure 4.…”

“…Table I. Loudness in sones as predicted by the models for ramped and damped envelopes for different carrier frequencies as used by Stecker and Hafter [44]. Additionally,level differences between ramped and damped signals at equal loudness as derivedf rom the loudness ratios are indicated in italics.…”

“…The comparison wasincluded in the present study because the models showc onceptual differences in the procedure to calculate loudness for this type of stimuli. Forthe loudness of temporally asymmetric stimuli, data of Stecker and Hafter [44] were used. Stecker and Hafter [44] showed that the auditory image model (AIM, [45])failed to predict this temporal aspect of loudness.…”

“…Forthe loudness of temporally asymmetric stimuli, data of Stecker and Hafter [44] were used. Stecker and Hafter [44] showed that the auditory image model (AIM, [45])failed to predict this temporal aspect of loudness. The present study investigates if this is also true for the twoe laborate loudness models.…”