Use of an adaptive noise canceler as an input preprocessor for a hearing aid.

The use of a two-channel adaptive noise canceler as a preprocessor for a hearing aid was evaluated. An omnidirectional microphone and a directional microphone were used as the inputs to the primary and reference channels, respectively, of the adaptive noise canceler. The microphones were mounted just above one ear on the head of a KEMAR mannikin. The system was found to work well under anechoic conditions, but showed only modest improvements in a moderately reverberant room (reverberation time 380 ms).