Duration discrimination and subjective duration for ramped and damped sounds

Abstract

The perception of stimuli with ramped envelopes (gradual attack and abrupt decay) and damped envelopes (abrupt attack and gradual decay) was studied in subjective and objective tasks. Magnitude estimation (ME) of perceived duration was measured for broadband noise, 1.0-kHz, and 8.0-kHz tones for durations between 10 and 200 ms. Damped sounds were judged to be shorter than ramped sounds. Matching experiments between sounds with ramped, damped, and rectangular envelopes also showed that damped sounds are perceived to be shorter than ramped sounds, and, additionally, the reason for the effect is a result of the damped sound being judged shorter than a rectangular-gated sound rather than the ramped sound being judged longer than a rectangular-gated sound. These matching studies also demonstrate that the size of the effect is larger for tones (factor of 2.0) than for broadband noise (factor of 1.5). There are two plausible explanations for the finding that damped sounds are judged to be shorter than ramped or rectangular-gated sounds: (1) the abrupt offset at a high level of the ramped sound (or a rectangular-gated sound) results in a persistence of perception (forward masking) that is considered in judgments of the subjective duration; and (2) listeners may ignore a portion of the decay of a damped sound because they consider it an "echo" [Stecker and Hafter, J. Acoust. Soc. Am. 107, 3358-3368 (2000)]. In another experiment, duration discrimination for broadband noise with ramped, damped, and rectangular envelopes was studied as a function of duration (10 to 100 ms) to determine if differences in perceived duration are associated with the size of measured Weber fractions. A forced-choice adaptive procedure was used. Duration discrimination was poorer for noise with ramped envelopes than for noise with damped or rectangular envelopes. This result is inconsistent with differences in perceived duration and no explanation was readily apparent.

The role of temporal-masking patterns in the determination of subjective duration and loudness for ramped and damped sounds

“…These results are consistent with those reported previously ͑DiGiovanni and Schlauch, 2007;Grassi and Darwin, 2006;Schlauch et al, 2001b͒. That is, damped sounds are perceived as being shorter than ramped sounds of equivalent duration.…”

“…1͒. Unlike the results of Schlauch et al ͑2001b͒, however, the present results show a greater difference in the ramped/damped matched duration when the ramped sound was the standard than when the damped sound was the standard ͑see Fig. 2͒.…”

“…2͒. The ramped/ damped duration ratios for the mid-duration stimuli ͑i.e., 25, 50, and 100 ms͒ when the ramped sound served as the standard are larger than those reported earlier ͑compare to the lower left panel of Schlauch et al, 2001b͒ than it follows their matching data. In addition, the results appear to be consistent with the results of Grassi and Darwin ͑2006͒ in that the difference in the perceived duration between ramped and damped stimuli of equivalent durations decreases for longer-duration stimuli ͑e.g., 200-500 ms in this study and 250-1000 ms in Grassi and Darwin's ͑2006͒ study͒.…”

Surveying the Temporal Structure of Sounds Used in Music Perception

“…Because the full explanation for these findings remains undetermined, other members of our research team are currently exploring this issue to further understand the underlying differences in the perceptual processing of tones differing only in their amplitude envelopes. This work will complement and extend previous studies demonstrating the effect of amplitude envelope in a variety of auditory perception tasks (Grassi & Casco, 2009;Neuhoff, 2001;Schlauch, Ries, & DiGiovanni, 2001). …”

Loudness Adaptation in Acoustic and Electric Hearing

“…Although the physiological mechanisms underlying loudness growth are not clear, they have been related to both cochlear and central nonlinearities (Fowler 1936;Zeng and Shannon 1994;Schlauch et al 1998;Schlauch et al 2001), as well as the total number and the timing of neural discharges in the auditory system (Fletcher 1940;Robinson and Dadson 1956;Carney 1994;Moore 1995;Relkin and Doucet 1997). Quantitative loudness models in acoustic and electric hearing have been proposed based on physiological data from the cochlear spread of excitation patterns and the auditory nerve activities (Zwicker and Scharf 1965;Bruce et al 1999a, b;Moore and Glasberg 2004).…”