Abstract: In a hearing aid having an oscillation detector and a method for establishing the presence of oscillations in a hearing aid, sinusoidal input signals of the microphone can be detected, and so oscillations that are present can also be detected. To this end, the number of digitized sample values in consecutive periods of the input signal is determined, and a long-term average value NL and a short-term average value NK are formed from these numbers. When NL and NK are essentially identical, the presence of oscillations is detected.

Abstract: In a hearing aid and method for automatically switching to a telephone mode, for automatically detecting a telephone situation for the wearer given a binaural supply, the difference between the levels of the input signals of the two hearing devices is measured and compared with at least one threshold value. If the difference in levels drops below or exceeds the threshold value, the respective hearing device is switched to the telephone mode.

Abstract: In a method for adapting a hearing aid, and a hearing aid arrangement for improving the directivity of a hearing aid with a number of microphones that are connected to one another for generating a directional characteristic, the hearing aid is exposed to acoustic waves in a room for precision measuring while the user is wearing it, and the directional characteristic is registered. The filter parameters that arise therefrom are supplied to parameterizable filters in the hearing aid that are connected downstream from the microphones, and the desired ideal directional characteristic can be approximated taking the individual conditions into account when the hearing aid is worn.

Abstract: A feedback compensator for a hearing aid device has a filter arrangement that splits a signal path, to implement an adaptive feedback compensation with only one buffer memory, two splitting nodes, and two addition nodes. The feedback compensation ensues only in the feedback-susceptible frequency range of the input signal. In addition to the filtering of the input signal, it is advantageous to feed to the adaptive feedback compensation filter a bandwidth-limited signal that is taken from the amplified output signal.

Abstract: A feedback compensator for a hearing aid device has a filter arrangement that splits a signal path, to implement an adaptive feedback compensation with only one buffer memory, two splitting nodes, and two addition nodes. The feedback compensation ensues only in the feedback-susceptible frequency range of the input signal. In addition to the filtering of the input signal, it is advantageous to feed to the adaptive feedback compensation filter a bandwidth-limited signal that is taken from the amplified output signal.

Abstract: In a hearing aid and method for automatically switching to a telephone mode, for automatically detecting a telephone situation for the wearer given a binaural supply, the difference between the levels of the input signals of the two hearing devices is measured and compared with at least one threshold value. If the difference in levels drops below or exceeds the threshold value, the respective hearing device is switched to the telephone mode.

Abstract: In a hearing aid, as well as in a method for the operation of a hearing aid having a microphone system in which different directional characteristics can be set, the tonal quality is improved, particularly in a quiet hearing environment, by the signal delay for at least one microphone signal being increased so as to increase the transfer function in the frequency response of the microphone system, thus also improving the signal-to-noise ratio, by decreasing the proportion of the microphone noise in the microphone output signal.

Abstract: The microphones used in hearing devices normally possess different characteristic lines that are to be adapted to one another. For this purpose, the amplitude of an output signal of a first microphone and the amplitude of an output signal of a second microphone are measured. The output signal of the first microphone is subsequently filtered dependent on both measured amplitudes, such that the difference between the two output signals is reduced. One of the two microphones hereby serves as a reference, and an absolute normalization can be foregone.

Abstract: A feedback compensator for a hearing aid device has a filter arrangement that splits a signal path, to implement an adaptive feedback compensation with only one buffer memory, two splitting nodes, and two addition nodes. The feedback compensation ensues only in the feedback-susceptible frequency range of the input signal. In addition to the filtering of the input signal, it is advantageous to feed to the adaptive feedback compensation filter a bandwidth-limited signal that is taken from the amplified output signal.

Abstract: In a method for producing a directional microphone characteristic and hearing aid device having a directional microphone characteristic, high-pass filters following two omnidirectional microphones are matched as to their limit frequencies for amplitude response and/or phase response of the two microphones. The limit frequency of the high-pass filter following one microphone is matched to the limit frequency of the other microphone.