Patent ID: 9641936
Date: 2017-05-02
CPC Classifications: G10K,H04R

Claim:
1. An indoor sound-modulating device comprising: a low-frequency noise detector for detecting low-frequency noise and generating a first modulating signal in response to the detected low-frequency noise; an automatic actuator issuing a second modulating signal in response to a predetermined state; and an audio signal generator in communication with the low-frequency noise detector and the automatic actuator, the audio signal generator generating a low-frequency audio signal for eliminating the low-frequency noise in response to the first modulating signal and generating a high-frequency repellent audio signal in response to the second modulating signal, the low-frequency audio signal having a frequency ranging from 20 Hz to 350 Hz, the high-frequency repellent audio signal having a frequency greater than or equal to 8000 Hz.