| 摘要 |
PURPOSE:To increase the articulation and to eliminate the operation for a hearing aid, by controlling a noise suppressor in accordance with the level of the ambient noise. CONSTITUTION:The voice including noise and applied to a microphone 11 is amplified by a preamplifier 12. A part of the output of the amplifier 12 is applied to an amplifying circuit 13 and a noise suppressor 14. At the same time, a part of the output of the amplifier 12 is applied to a filter 16. Thus only the noise component is extracted. The level of the noise component is compared with the reference voltage 20. When the level of the noise component is higher than the voltage 20, an electronic switch 15 selects the output of the device 14 to use it as an output. |
