Share how to choose noise reduction headphones

Noise reduction headphones on the market are divided into active noise reduction and passive noise reduction.

Passive noise reduction headset

It mainly uses physical properties to isolate external noise from the ear, and prevents noise from entering the ear through obstructions of different materials, just like setting off firecrackers and covering the ear with your hand.

Advantages:

It is very effective for high-frequency noise. Generally, it can reduce the noise by about 15-20db. This noise reduction method is the most traditional and common, and its price is the cheapest compared with active noise reduction headphones.

The noise reduction space is large, and the passive noise reduction has a good isolation effect on high-frequency signals, so the noise reduction space is large. For example, the soundproof panel beside the highway. However, for the low-frequency noise in small space, the effect of noise such as air conditioning working noise and aircraft engine noise is greatly reduced.

inferiority:

It is impossible to neutralize noise. Most portable sound isolating earphones we can see are passive noise reduction methods. In ear earplugs and closed earphones can isolate noise to a certain extent, but there is no way to neutralize noise to achieve quiet listening effect.

The tone is too large. In order to improve the noise reduction effect, many passive noise reduction headphones turn up the original sound to eliminate the noise, which is not very good for ear health. This requires you to carefully check and compare the tone of noise reduction headphones.

Active noise reduction headset

The theory of active noise reduction headphones is very simple. All sounds are composed of a certain spectrum. If you can find a sound, its spectrum is exactly the same as the noise to be eliminated, but the phase is just opposite (180 °), you can completely cancel the noise. Active noise reduction uses digital signal processing (DSP) to eliminate external noise. This technology is to build a micro microphone and an acoustic processor in the headset. When there is noise around, active noise reduction will create a completely opposite sound through the processor to neutralize and eliminate the noise. In acoustics, this is called "cancellation interference".

Advantages:

The sound quality is pure and beautiful. Active noise reduction makes up for the lack of passive noise reduction in low-frequency noise reduction, and brings users more pure and beautiful sound quality. For example, the noise in public places, the rumble of cars and trains, etc., are more suitable for the user's use of the scene.

Protect users' hearing. The active noise reduction headset is equipped with a dedicated noise reduction circuit, including a customized high-sensitivity MEMS silicon microphone and a professional noise reduction chip, which can offset the noise by receiving and analyzing the external noise spectrum and generating signals with opposite phases. Why do you say so? We assume that the surrounding noise (DB) is constant, and the volume of the mobile phone that can meet the listening needs without noise reduction headphones is 20 bars; After changing to noise reduction headphones, as the noise is reduced, only 10 grids are needed to meet the listening needs. So from this point of view, noise reduction headphones have a very prominent protective effect on hearing.

inferiority:

The cost is high, but the necessary equipment of the active noise reduction system includes pickup, processing chip and loudspeaker. Each part must ensure high quality to achieve the final effect, so the cost is higher.

Energy consumption. There are acoustic processors in the active noise reduction headset, so turning on the active noise reduction mode will have some adverse effects on the endurance of the wireless headset.