Tolerance for Pure Tones and Speech in Normal and Hard-of-Hearing Ears

Abstract : The investigation represents a systematic study of the quantitative and qualitative nature of the tolerance limits for speech and pure tones of normal and deafened ears. With reference to the Aural Rehabilitation Program of the armed forces, the tests were made to yield data pertinent to the design characteristics of future hearing aids, and to provide information which would guide procedures in the clinical selection of hearing aids. The threshold of discomfort, tickle, and pain produced by pure tones and speech were determined in approximately 16,000 observations on 46 normal and 46 hard-of-hearing cases, the latter representing fairly balanced distribution of clinical types of deafness. The results of the tests are summarized and tabulated, and the data indicate that 130 db appears to be the greatest useful maximum output in a hearing aid.