Passive Noise Cancellation(PNC):
Passive Noise Cancellation is the noise that headphones block out based on the physical design of the earcups. In short, a relatively closed space is formed between the sound generating unit and the ear, and some sound insulation materials such as fillers are used to block the external noise. It is used most heavily in the headphones market.
Advantages:
It can greatly reduce high-frequency noise.
Disadvantages:
1. For some low-frequency noise, the isolation effect is not good.
2. The effect of passive noise cancellation will be reduced in the vehicle or engine room.
Active Noise Cancellation(ANC):
Active noise cancellation is a method of noise reduction. The propagation of sound is realized through the vibration of the medium. If there is an inverse phase between waves, it will be offset under theoretical conditions. The principle of active noise reduction is to send out completely opposite sound waves according to the specified noise, so that the two sound waves offset each other when they meet, so as to isolate the noise.
Advantages:
It can eliminate the background noise with low frequency.
Disadvantages:
1. High price
2. Since the active noise cancellation earphone will send out additional sound waves to offset the noise, the sound details will be lost and the sound quality will be discounted.
3. The active noise cancellation earphone contains an acoustic processor, etc., so turning on the active noise reduction mode will speed up the power consumption of the wireless earphone.
