The active noise reduction, also known as ANC (Active Noise Control). Its basic principle is that the noise reduction system generates reverse sound waves equal to the external noise to neutralize the noise. In the automotive industry, it can be used for the tube noise reduction.
ANC Schematic Diagram
Tube Noise Reduction
The tube noise reduction system is mainly realized by ANC in the automotive industry. In this system, the reference microphone obtain the reference signal of noise, and generate the control signal after being processed by the data acquisition instrument and the computer (adaptive filtering), and then, output it to the secondary sound source to drive the speaker to produce offset sound to minimize the noise signal at the error microphone.