There are two methods for earphone noise reduction, active noise reduction and passive noise reduction.
The active noise reduction function is to generate inverted sound waves equal to external noise through the noise reduction system, neutralizing the noise, and achieving noise reduction effects. Active noise reduction earphones are equipped with noise reduction circuits that compete with external noise. Most of them adopt a larger headworn design, which can use structures such as earplug cotton and earphone housing to block external noise for the first round of sound insulation. At the same time, active noise reduction circuits and power supplies are installed in order to have sufficient space.
Passive noise reduction earphones mainly surround the ear to form a closed space, or use soundproofing materials such as silicone earplugs to block external noise. Due to the fact that the noise has not been processed by the noise reduction circuit chip, it can generally only block high-frequency noise, and the noise reduction effect on low-frequency noise is not obvious.
