摘要:

In most previous experiments on the ability to identify sound intensity, the stimulus set has been chosen such that the range of intensities is many times larger than the value of the “just‐noticeable difference” in intensity that has been derived from the results of intensity discrimination experiments. In such cases, the resolution obtained in the identification experiment is much worse than would be expected merely on the basis of the pairwise discriminability of the stimuli. In this paper, we report the results of a study designed to explore the prediction [Durlach and Braida, J. Acoust. Soc. Amer.46, 372–382 (1969)] that this discrepancy between identification and discrimination does not occur if the range of intensities employed in the identification experiment is sufficiently small. Generally speaking, the results of this study support the prediction.

ISSN:0001-4966    

DOI:10.1121/1.1912878

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

This research attempts to replicate the report of Carterette, Friedman, and Lovell [J. Acoust. Soc. Amer.45, 986–998 (1969)] who indicated the existence of auditory masking effects similar to Mach bands in vision. Threshold for sinusoids in narrow bands of noise were estimated for five listeners using an adaptive psychophysical procedure. The data show little, if any, similarity to Mach band effects, but rather are in line with what would be expected based on a traditional critical band concept.

ISSN:0001-4966    

DOI:10.1121/1.1912879

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

The calculation procedure Mark VII gives the perceived level of loudness or noisiness in PLdB. It utilizes a set of frequency‐weighting contours based on an average of 25 experimental contours. The standard reference sound is defined as a13‐octband centered at 3150 Hz. The perceived magnitude (loudness or noisiness) grows as the23power of the sound pressure, so that perceived magnitude doubles with each increase of 9 dB. The summation formula for the total subjective magnitude remainsSt = Sm + F (∑S − Sm), but the value ofFis made to vary as a function of level in order to reflect the nonlinear growth (in log‐log coordinates) of broad‐band noise. As a result of the new reference sound at 3150 Hz, perceived level in decibels (PLdB) is approximately 8 dB lower than the older loudness level in phons. Except for the nearly constant difference of 8 dB, Mark VI and Mark VII give closely similar results for typical broad‐band noises. The 8‐dB downward shift makes it possible for a sound level meter with an “ear weighting” to give readings (E) in decibels within a decibel or two of perceived level in PLdB. With the frequency‐weighting contours extended down to 1.0 Hz, Mark VII also provides a procedure for calculating the perceived levels of sonic booms and other impulse noises.

ISSN:0001-4966    

DOI:10.1121/1.1912880

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

Perstimulatory loudness adaptation was measured by two techniques which utilized varying amounts of simultaneous contralateral stimulation. In the first experiment a single‐SDLB (simultaneous dichotic loudness balance) method was employed with comparison signals of 200‐ and 2000‐msec duration and with an adapting signal of 8 sec. More adaptation was noted when the longer comparison signal was employed. In the second experiment, a modified tracking procedure utilized comparison signal duty cycles of1623%and 50%. The higher duty cycle yielded a greater magnitude of test‐ear adaptation than did the lower duty cycle. The results support the hypothesis that perstimulatory loudness adaptation is dependent on simultaneous binaural stimulation and, in addition, is related to the amount of that stimulation. It is therefore concluded that adaptation is not a monaural or a purely peripheral phenomenon.

ISSN:0001-4966    

DOI:10.1121/1.1912881

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

An experiment is described in which perstimulatory loudness adaptation is measured by delayed balance and by single simultaneous balance methods. The adapting signals consisted of all combinations of intensity (sound‐pressure level 30, 50, 80, and 100 dB), frequency (250, 1000, and 4000 Hz), and duration (1, 2, 4, 8, 12, 16, and 30 sec). The results reveal little adaptation with simultaneous balances and slightly negative adaptation with delayed balances. Duration of the adapting signal had no significant effect on the data. However, the differences between methods of measurement, intensities, and frequencies of the adapting signal were statistically significant. All interactions, except those involving the duration factor, were statistically significant.

ISSN:0001-4966    

DOI:10.1121/1.1912882

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

To test the “variable‐resistance” theory of production of cochlear microphonics, the impedance variation between scala media and the neck of guinea pigs was measured during low‐frequency sound stimulation. Results show an impedance variation at the sound frequency that can be as large as 100 Ω (1% of the dc impedance) occurring in the walls of the endolymphatic space. This supports the concept that the cochlear microphonic potentials are produced because of resistance change at the reticular lamina.

ISSN:0001-4966    

DOI:10.1121/1.1912883

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

Binaural unmasking behavior was investigated at suprathreshold levels using 250‐ and 500‐Hz sinusoids. First, the traditional detection masking‐level difference (MLD) was measured; then a loudness balance was made between the masked S0 and Sπ signals at four sensation levels to infer the superthreshold binaural advantage. The results showed that the antiphasic advantage decreased with the increasing sensation level of the signals and implied that the loudness of the masked antiphasic signals grew more slowly than that of the masked homophasic signals. The influence of this loudness effect on other data in the literature is discussed.

ISSN:0001-4966    

DOI:10.1121/1.1912884

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

Moray [J. Acoust. Soc. Amer.47, 660–661; 1071–1073 (1970)] has presented data on the detection of binaural tone increments which he interprets in terms of an attention‐switching model. The data are re‐examined and it is shown that they cannot easily be reconciled with this model. An alternative hypothesis is presented. This assumes that the input to the two ears is processed in parallel, and that different response criteria are applied to the detection of unilateral and bilateral signals. This account appears to give a more satisfactory and more parsimonious account of the data.

ISSN:0001-4966    

DOI:10.1121/1.1912885

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

This paper attempts to show that the traveling waves along the basilar membrane increase the relatively small amplitude of the first harmonic in Seebeck's experiment, so that the unexpected loudness of the first harmonic is of physical origin and does not contradict the place theory of hearing.

ISSN:0001-4966    

DOI:10.1121/1.1912886

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

Predictions, inferred from Small's model, of significantly lower auditory adaptation when test‐tone intensity exceeds adapting‐tone intensity were confirmed. Adaptation effects with test and adapting tone equal in intensity increased between 40 and 60 dB and remained relatively constant between 60 and 80 dB. When adapting‐tone intensity exceeded test‐tone intensity, previous findings that adaptation does not increase generally were confirmed. Theoretical implications of the results are discussed.

ISSN:0001-4966    

DOI:10.1121/1.1912887

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP