| 摘要 |
2111829 9300779 PCTABS00019 An improved audio compressor (100) of the type which is useful in a hearing aid and having a programmable compression ratio is disclosed. In the preferred embodiment, the compressor is used in a hearing aid device of the type which comprises a bandsplit filter (106) to divide an input audio signal into a plurality of frequency bands (108, 110). Associated with each frequency band is a limiter means (220) which provides variable gain amplification of the input signal as a function of the amplitude of the input signal and as a further function of a programmable control signal. A feedforward means (206) is disposed in parallel to the limiter means (220), said feedforward (206) means providing a fixed gain signal. The output of the limiter means and the feedforward means are combined at a summing node (212) which forms the input to a variable gain amplifier. Associated control circuitry allows to limiter gain to be programmed to meet the needs of an individual user. The compressor has a variable compression ratio in the form of a sigmoid function.
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