File:Bell telephone magazine (1922) (14570066019).jpg

Identifier: belltelephonemag19amerrich (find matches)
Title: Bell telephone magazine
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

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30-39, and 50-59 yeargroups. Young men and women hearabout equally well at low frequencies,but the women hear about 3 db bet-ter at 7040 cycles per second. Thedifference is much more pronounced,however, in the older group, wheremen hear about 3 db better at lowfrequencies, while the reverse holdsat the higher ones to the extent offrom 5 to 10 db. Zero hearing lossin all of these tests is taken as thehearing acuity of the average of bothmen and women in the 20-29 yeargroup. This reference level corre-sponds closely to that for no hearingloss on the 2A Audiometer. Test cards, as they appear for theaverage woman and man for thegroup 50-59 years, are shown on page269. The lighter numbers at theleft of each column are those writ-ten down by the person tested, as helistened to the tone pulses. Theheavier numbers at the right arethose which become visible whenlight passes through the card; theyshow the number of pulses actuallysounded. Loss of hearing is indi- 19^0 Testing Americas Ears 271
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RECORDING RESULTS FROM TEST CARDS The cards were recorded on 16-mm film, and results were later transferred to punch cardsby an operator who viewed the film in a projector cated by the numerous blank spacesin the last two columns. The aver-age young person could hear the firstsix or seven tone steps but missed thefaintest two or three. From 10 to15 per cent of the youngest group,however, and from 1 to 2 per cent ofthe oldest group, could hear the faint-est sounds. Ihe ability to understand speechusually can be predicted from theaverage hearing loss up to 1,760 cy-cles per second. An indication of thesignificance of hearing losses of vari-ous magnitudes may be obtained fromthe collective judgment of deafenedpeople as reported in a survey con-ducted several years ago by theUnited States Public Health Service.In that survey, people with hearing losses of 25 db or higher reporteddifficulty in hearing in auditoriumsand churches. Difficulty in hearingdirect conversation when the speakeris t

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