Abstract: A hearing aid has a sound-receiving microphone from which an incoming signal is supplied to a number of different channels, each channel being allocated to a different frequency range within a total expected range of frequencies for the incoming signal. Each channel includes a circuit for measuring the strength of the signal within the frequency range for that channel and for changing the respective strengths of the signals in the other channels by suppressing weak signal channels in favor of strong signal channels.

Abstract: To improve the fidelity of reproduction of automobile radios during conditions of extraneous in the passenger compartment, noise signals are derived, for example from a microphone installed in the engine compartment of the vehicle. The audio program signals are conducted through a multichannel equalizer; the program audio signals and the noise signals are separated into a plurality of frequency bands, for example three bands, the envelope of which are demodulated and the derived demodulation signals are instantaneously compared to then control the transfer characteristics of the respective bands of the equalizer in accordance with the derived comparison between the respective bands of the noise and program signals. Preferably, amplitude, change of transfer amplitude and rate of change is controlled by weighting the comparison signals and the rate of change thereof in relation to the frequency bands and the extent of change of the signals.

Abstract: A tactile hearing aid has electro-mechanical transducers which emit vibrations to the sense of touch of the skin surface for the transmission of signals. The transducers are small and lightweight and have low power consumption. The vibratory member is composed of piezoelectric, high-polymer material and has the form of a film which is provided with electically conductive coatings at both sides between which the signals to be transmitted can be applied. The film may be bent to form a ring and may be arranged in a folded stack of a number of plies to the outside surface of a carrier ring which is approximately 90.degree. open. The transducer can thus be worn on the fingers of a hand. The transducer unit is employable with particular advantage in devices for the transmission of messages via the sense of touch such as in hearing prothesis for persons extremely hard of hearing or for deaf persons.

Abstract: A hearing aid which can be built into a frame, such as eyeglasses, to be worn by a hearing-impaired person has a first microphone arrangement having a directional reception pattern, and a second microphone arrangement for sound locating. The second microphone arrangement includes a first locating microphone disposed in the region of one ear of the hearing-impaired person, and a second locating microphone disposed in the region of the other ear. The signal from both locating microphones are mixed by a low-pass filter with the signal from the microphone arrangement having a directional reception pattern, and the output of the mixing operation is supplied in common to both ears of the hearing-impaired person.

Abstract: A directional microphone arrangement has a number of discrete microphones each having an electrical output and elements for deriving first and second electrical signals which are 180.degree. out of phase with respect to each other from the outputs of the microphones. A third signal is also derived through differentiation from one of the microphone outputs which is 90.degree. out of phase with respect to one of the first or second signals. All of the first, second and third signals are added in a summing unit, the output of the summing unit forming the output for the arrangement.

Abstract: In the exemplary embodiments, the sound signals are converted into electrical signals, which are wirelessly transmitted to an implanted receiver, and from the latter, electric stimuli in electrode channels are brought to act on the auditory nerve. The transmission proceeds in the time division multiplex technique in such a manner that the electrical signals are subjected to a pulse modulation and are transmitted in an HF-channel. Thus, the receiver can be reduced with regard to the volume of its construction as well as with regard to its energy requirement. The disclosed method and hearing prostheses for its realization are particularly suited for attending to the needs of the extremely hard of hearing.

Abstract: Speech recognition is improved by time-standardization of reference and unknown words of constant bit-length formed by suppressing bits or generating copy bits.

Abstract: In the illustrated embodiments, the signals to be transmitted are converted into electrical signals and are divided by means of filters into a plurality of frequency bands. The envelopes of the signals coming out of the filters are then employed for the modulation of tones. Finally, the original tones and the modulated tones are supplied to the hearing-impaired person as an audio signal. To this end, the disclosure provides that the original signal to be transmitted is transmitted together with the modulated tones, and that the ratio of the volumes of the original tones and those of the modulated tones is set to a ratio which is comfortable for the hearing-impaired person. The transmission of the modulated tones is at least partially interrupted for voiced sounds. Standard ear sets or implanted devices with direct electrical transmission of the signals to the auditory nerve can be employed for transmission to the hearing-impaired person.

Abstract: In an exemplary embodiment, the point of departure is that of a substitute signal system for deaf individuals which codes acoustical signals, in particular speech sound, into electrocutaneous stimulation patterns. Current pulse patterns serve as substitute signals which, via skin surface electrodes, e.g. on the forearm, bring about sensory patterns which can be interpreted as speech information. To this end, the sound signal is separated with band pass filters into e.g. twelve component signals characteristic for the recognition of speech, whose levels are converted into pulse durations, whereby the dependency of the sensation intensity upon the stimulation parameters is taken into account. The mean frequencies of the band pass filters are associated with a corresponding number of locations on the forearm (i.e. in the present example twelve). A simulation of lateral inhibition suppresses irrelevant spectral components and thus acts in a selectivity-increasing (or enhancing) fashion.

Abstract: In an exemplary embodiment, for testing the chronological resolution of hearing, acoustic signals are supplied to the ear to be tested via an earpiece and consist of a test tone which can be interrupted and of a masking sound which can be modulated, their frequency and amplitude level being adjustable. Complicated measures are necessary for the measurement of the so-called listening threshold period pattern in order to present a complete pattern for identifying the chronological resolution of the hearing. In contrast, the disclosure provides an uncomplicated measuring device which is also easy to operate and with which the maximum and the minimum of the listening threshold period pattern or, respectively, their difference can be determined. To this end, the disclosure provides a device with channels generating respective sound signals, each of the channels having its own generator.

Abstract: In an exemplary embodiment, the signals to be transmitted are converted into electric signals and resolved into a multiplicity of frequency bands by means of filters. The signals coming from the filters are then employed for the modulation of tone signals. Finally, original tones are supplied to the person hard of hearing together with the modulated tones as the auditory signal. To this end, the disclosure provides that the resolution ensues into at least three frequency bands and that the frequencies of the modulated tones are adapted to the residual frequency band of the person hard of hearing and that all of the signals to be transmitted are transmitted together with the modulated tones and that the ratio of the loudness of the original tones and that of the modulated tones is set at a ratio which is useful for the person hard of hearing.