The input/output formula: a theoretical approach to the fitting of personal amplification devices.
There is a growing trend for hearing aids to incorporate wide dynamic range compression. The input/output (I/O) hearing aid formula, presented in this report, is a general frequency-specific mathematical approach which describes the relationship between the input level of a signal delivered to a hearing aid and the output level produced by the hearing aid. The I/O formula relates basic psychoacoustic parameters, including hearing threshold level and uncomfortable listening level, to the electroacoustic characteristics of hearing aids. The main design goal of the I/O formula was to fit the acoustic region corresponding to the "extended" normal auditory dynamic range into the hearing-impaired individual's residual auditory dynamic range. The I/O approach can be used to fit hearing aids utilizing linear gain, linear compression or curvilinear compression to a hearing-impaired individual's residual auditory area.
Cornelisse
L E
LE
Department of Communicative Disorders, University of Western Ontario, London, Canada.
Seewald
R C
RC
Jamieson
D G
DG
D001309:Auditory Threshold; D012048:Correction of Hearing Impairment; D006310:Hearing Aids; D006801:Humans; D008962:Models, Theoretical; D013067:Speech Perception