Methods for Limiting the Maximum Output of Hearing Aids Harvey Dillon(1),
Inge Roe(1), Denis Byrne(1) and Herbie Baechler(2) The maximum output of hearing aids can be controlled by at least three different techniques. These comprise peak clipping, fast acting compression limiting, and slow-acting compression limiting. In addition, combinations of any of these can be used. A series of field and laboratory experiments were conducted to determine which types or combinations of limiting were preferred by 19 experienced hearing aid wearers with moderate to profound hearing losses. The most definite results were obtained from the paired-comparison experiment carried out in the laboratory. When peak clipping was compared to fast acting compression limiting and to a combination of these two limiting methods, peak clipping alone was the least preferred limiting method. There appears to be no reason to use peak clipping except when the highest possible output SPL is required. The addition of slow-acting compression limiting was significantly preferred by many subjects, and there were no subjects for whom this decreased the acceptability of the hearing aid. |