Abstract
The concept of loudness recruitment widely accepted as an abnormal auditory phenomenon does not appear to be justified. Experimental results provided by Stevens and Davis (1938) adequately show that the phenomenon of recruitment is not abnormal. The data shown in the loudness function curve (Stevens and Davis, 1938, p. 118) reveals that the loudness level of 1000 Hz. tone at 40, 70, and 100 dB. SPLs is approximately 1, 10 and 100 sones respectively for normal subjects. Therefore, if an individual has a sensorineural loss of about 40 dB SPL (equal to one sone), there will be loudness loss of I sone throughout the intensity range. That is, he will perceive a tone of 70 dB SPL at a loudness level of 9 sones and a tone of 100 dB SPL at a level of 99 sones. Thus the difference in the loudness perceived by the normal and the abnormal ears is very small.
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