Influence of Age on the Ability to Hear Telephone Ringers of Different Spectral Content

Abstract

The failure to detect a telephone ringer signal can prove frustrating or even hazardous in certain situations, especially for older individuals who rely heavily on telephone access. This study was conducted to investigate the detectability of telephone ringer signals with individuals having elevated hearing levels. Specifically, the study investigated the detectability of three acoustically different telephone ringer signals under two masking noise conditions (quiet and 65 dBA pink noise) for two subject age groups: 20–30 years of age and over 70 years of age. Common residential telephone ringers were sampled, with three acoustically different ringers selected for study. To determine hearing ability, pure tone audiograms were administered to all subjects. Subjects' threshold levels for each ringer were then determined. Significant differences were found between the two age groups, both across telephone ringers and across noise conditions. For the older group, an advantage was found for the ringer signal which contained prominent low-to-mid range frequency components. In addition, the threshold level in noise of one ringer (a high frequency “beeper” type ringer) proved to be approximately equal to the naturally occurring decibel level of that ringer. Thus, the beeper ringer in moderate level noise (65 dBA) was effectively inaudible. The results suggest that certain electronic ringers which are currently in vogue may be unsuitable for use by the elderly or by any individual with significant high-frequency hearing loss.