Compression systems for hearing aids
First Claim
1. A hearing aid device for the compensation of hearing deficiencies of a hearing impaired individual comprising:
- an input transducer for converting acoustic energy into an electrical input signal;
an output transducer for converting received electrical signals into an acoustic output signal;
a linear amplifier for receiving the input signal and amplifying it at a fixed gain to produce a linearly amplified signal;
one or more compression amplifiers each receiving and amplifying a respective component of the input signal to produce a compressed signal, each compression amplifier having variable gain, the linearly amplified signal being supplied to the output transducer without being received or amplified by the one or more compression amplifiers; and
an adjustable volume control receiving the one or more compressed signals without receiving the linearly amplified signal and adjusting the gain of the one or more compressed signals without adjusting the gain of the linearly amplified signal to produce a volume adjusted signal, the volume adjusted signal being supplied to the output transducer.
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0 Petitions
Accused Products
Abstract
A hearing aid circuit using an averaging detector and a plurality of time constants to produce a compression control signal to control the gain of a compression amplifier which compresses an input signal when the averaging detector signal exceeds a predetermined threshold. The compression control signal has an attack and release time. The release time of the compression control signal is proportional to the duration of time during which the averaging signal'"'"'s amplitude exceeds the predetermined threshold level. The release has a variable recovery rate. The recovery rate is relatively fast during an initial portion of the release time and relatively slower during the remaining portion of the release time. The hearing aid circuit may also use a volume control to adjust the gain of the signal produced by the compression amplifier without adjusting the gain of the signal produced by a linear amplifier to provide volume control for soft sounds independent of loud sounds.
95 Citations
57 Claims
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1. A hearing aid device for the compensation of hearing deficiencies of a hearing impaired individual comprising:
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an input transducer for converting acoustic energy into an electrical input signal; an output transducer for converting received electrical signals into an acoustic output signal; a linear amplifier for receiving the input signal and amplifying it at a fixed gain to produce a linearly amplified signal; one or more compression amplifiers each receiving and amplifying a respective component of the input signal to produce a compressed signal, each compression amplifier having variable gain, the linearly amplified signal being supplied to the output transducer without being received or amplified by the one or more compression amplifiers; and an adjustable volume control receiving the one or more compressed signals without receiving the linearly amplified signal and adjusting the gain of the one or more compressed signals without adjusting the gain of the linearly amplified signal to produce a volume adjusted signal, the volume adjusted signal being supplied to the output transducer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28)
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29. A hearing aid device for the compensation of hearing deficiencies of a hearing impaired individual comprising:
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an input transducer for converting acoustic energy into an electrical input signal; an output transducer for converting received electrical signals into an acoustic output signal; a linear amplifier for receiving the input signal and amplifying it at a fixed gain to produce a linearly amplified signal; one or more compression amplifiers each receiving and amplifying a respective component of the input signal to produce a compressed signal and having a variable gain, the linearly amplified signal being supplied to the output transducer without being received or amplified by the one or more compression amplifiers; and an adjustable volume control receiving the one or more compressed signals without receiving the linearly amplified signal and adjusting the gain of the one or more compressed signals without adjusting the gain of the linearly amplified signal to produce a volume adjusted signal, the volume adjusted signal being supplied to the output transducer.
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30. A hearing aid device for the compensation of hearing deficiencies of a hearing impaired individual comprising:
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an input transducer for converting acoustic energy into an electrical input signal; an output transducer for converting received electrical signals into an acoustic output signal; a linear amplifier for receiving the input signal and amplifying it at unity gain to produce a linearly amplified signal; two or more compression amplifiers each receiving and amplifying a respective component of the input signal to produce a compressed signal, the two or more compression amplifiers each having variable gain, the linearly amplified signal being supplied to the output transducer without being received or amplified by the two or more compression amplifiers; two or more bandpass filters for receiving the input signal and supplying to the respective compression amplifiers the respective components of the input signal, each respective component of the input signal being a different frequency band of the input signal; and an adjustable volume control receiving the one or more compressed signals without receiving the linearly amplified signal and adjusting the gain of the two or more compressed signals without adjusting the gain of the linearly amplified signal to produce a volume adjusted signal, the volume adjusted signal being supplied to the output transducer.
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31. A signal processing system for use in a hearing aid to compensate for hearing deficiencies of a hearing impaired individual, comprising:
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a linear amplifier for receiving an input signal and amplifying it at a fixed gain to produce a linearly amplified signal; one or more compression amplifiers each receiving and amplifying a respective component of the input signal to produce a compressed signal, the one or more compression amplifiers each having variable gain, the linearly amplified signal being supplied to an output without being received or amplified by the one or more compression amplifiers; and an adjustable volume control receiving the one or more compressed signals without receiving the linearly amplified signal and adjusting the gain of the one or more compressed signals without adjusting the gain of the linearly amplified signal to produce a volume adjusted signal, the volume adjusted signal being supplied to the output, thereby amplifying input signals below a loud signal threshold at at least unity gain and amplifying input signals above the loud signal threshold at substantially unity gain.
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32. A signal processing system for use in a hearing aid to compensate for hearing deficiencies of a hearing impaired individual, comprising:
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a linear amplifier for receiving an input signal and amplifying it at a fixed gain to produce a linearly amplified signal; a compression amplifier for receiving and amplifying a respective component of the input signal to produce a compressed signal, the compression amplifier having variable gain, the linearly amplified signal being supplied to an output without being received or amplified by the compression amplifier; and an adjustable volume control receiving the compressed signal without receiving the linearly amplified signal and adjusting the gain of the compressed signal without adjusting the gain of the linearly amplified signal to produce a volume adjusted signal, the volume adjusted signal being supplied to the output, thereby amplifying input signals below a loud signal threshold at at least unity gain and amplifying input signals above the loud signal threshold at substantially unity gain.
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33. A hearing aid device for the compensation of hearing deficiencies of a hearing impaired individual comprising:
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an input transducer for converting acoustic energy into an electrical input signal; an output transducer for converting received electrical signals into an acoustic output signal; one or more compression amplifiers each receiving and amplifying a respective component of the input signal to produce a compressed signal which is supplied to the output transducer, each compression amplifier having variable gain dependent upon a compression control signal; an averaging detector for generating an averaging signal indicative of a time-average value of the one or more compressed signals; and a plurality of time constant means coupled to the averaging detector providing diverse time constants which together produce the compression control signal, the compression control signal progressively reducing the gain of each compression amplifier as the averaging signal exceeds a predetermined threshold level, the compression control signal having a relatively shorter attack and a relatively longer release time, the release time being proportional to the duration of the period of time during which the amplitude of the averaging signal exceeds the predetermined threshold level, the release time having a variable release rate being relatively faster during an initial portion of the release time and relatively slower during a remaining portion of the release time. - View Dependent Claims (34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52)
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53. A hearing aid device for the compensation of hearing deficiencies of a hearing impaired individual comprising:
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an input transducer for converting acoustic energy into an electrical input signal; an output transducer for converting received electrical signals into an acoustical output signal; a compression amplifier for receiving and amplifying the input signal to produce a compressed signal which is supplied to the output transducer, the compression amplifier having variable gain dependent upon a compression control signal; an averaging detector for generating an averaging signal indicative of a time-average value of the compressed signal; and at least first and second time constant means provided by a plurality of resistors and capacitors, the at least first and second time constant means coupled to the averaging detector providing at least two different time constants which together produce the compression control signal, the compression control signal progressively reducing the gain of the compression amplifier as the averaging signal exceeds a predetermined threshold level, the compression control signal having a relatively shorter attack and a relatively longer release time, the release time being proportional to the duration of the period of time during which the amplitude of the averaging signal exceeds the predetermined threshold level, the attack time in the range of about 0.001-0.3 seconds and the release time in the range of about 0.02-0.5 seconds for input signals of about 0.1 seconds and of about 0.5-1.5 seconds for input signals of about 2.0 seconds, the release time having a variable release rate being very fast during an initial portion of the release time and relatively slow during a remaining portion of the release time.
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54. A signal processing system for use in a hearing aid to compensate for hearing deficiencies of a hearing impaired individual, comprising:
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one or more compression amplifiers each receiving and amplifying a respective component of an input signal to produce a compressed signal which is supplied to an output, each compression amplifier having variable gain dependent upon a compression control signal; an averaging detector for generating an averaging signal indicative of a time-average value of the one or more compressed signals; and a plurality of time constant means coupled to the averaging detector providing diverse time constants which together produce the compression control signal, the compression control signal progressively reducing the gain of each compression amplifier as the averaging signal exceeds a predetermined threshold level, the compression control signal having a relatively shorter attack and a relatively longer release time, the release time being proportional to the duration of the period of time during which the amplitude of the averaging signal exceeds the predetermined threshold level, the release time having a variable release rate being relatively faster during an initial portion of the release time and relatively slower during a remaining portion of the release time.
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55. A signal processing system for use in a hearing aid to compensate for hearing deficiencies of a hearing impaired individual, comprising:
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a compression amplifier for receiving and amplifying an input signal to produce a compressed signal which is supplied to an output, the compression amplifier having variable gain dependent upon a compression control signal; an averaging detector for generating an averaging signal indicative of a time-average value of the input signal; and a plurality of time constant means coupled to the averaging detector providing diverse time constants which together produce the compression control signal, the compression control signal progressively reducing the gain of the compression amplifier as the averaging signal exceeds a predetermined threshold level, the compression control signal having a relatively shorter attack and a relatively longer release time, the release time being proportional to the duration of the period of time during which the amplitude of the averaging signal exceeds the predetermined threshold level, the release time having a variable release rate being relatively faster during an initial portion of the release time and relatively slower during a remaining portion of the release time.
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56. A hearing aid device for the compensation of hearing deficiencies of a hearing impaired individual comprising:
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an input transducer for converting acoustic energy into an electrical input signal; an output transducer for converting received electrical signals into an acoustic output signal; one or more compression amplifiers each receiving and amplifying a respective component of the input signal to produce a compressed signal which is supplied to the output transducer, each compression amplifier having variable gain dependent upon a respective compression control signal; one or more averaging detectors each generating an averaging signal indicative of a time-average value of the respective compressed signals; and a plurality of time constant means coupled to each averaging detector providing a plurality of sets of diverse time constants, the diverse time constants of each set of diverse time constants together defining the respective compression control signals, each compression control signal progressively reducing the gain of each respective compression amplifier as the respective averaging signal exceeds a predetermined threshold level, each compression control signal having a relatively shorter attack and a relatively longer release time, each release time being proportional to the duration of the period of time during which the amplitude of the respective averaging signal exceeds the predetermined threshold level, each release time having a variable release rate being relatively faster during an initial portion of the respective release time and relatively slower during a remaining portion of the respective release time.
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57. A method of processing a hearing aid signal to compensate for the hearing deficiencies of a hearing impaired individual comprising:
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converting acoustic energy received by an input transducer into an electrical input signal; providing the electrical input signal to a first signal path having a fixed gain to produce a linearly amplified signal; providing the electrical input signal to one or more compression signal paths, each of the one or more compression signal paths parallel to the first signal path, each of the one or more compression signal paths including a compression amplifier which amplifies the input signal to produce a compressed signal, each compression amplifier having variable gain; volume adjusting each compressed signal without adjusting the gain of the linearly amplified signal in the first signal path to produce a volume adjusted signal in each of the one or more compression signal paths; and providing the volume adjusted signals and the linearly amplified signal to an output transducer.
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Specification