Abstract
The absolute thresholds for hearing were measured by small earphone which was calibrated in 2cc coupler in 16 deaf children with and without hearing aids. And the differences of these values at each frequency were compared with the gains of the hearing aid.
Theoretically the differences must be corresponded with the gain of the aid, but practically they were not. If difference of 10dB was allowable, 91% of cases showed no differnce of these values.
