Data show that the noise level rapid 3d prototyping at bus stops and subway entrances is 84-86dB, while the noise level in buses, subway stations and their family cars are 80dB, 77dB and 72dB respectively.In other words, the morning and evening rush hour, you stand in the bus light, next to the ear is 80dB up and down the noise, if you listen to a song, a phone call, cell phone headphones sound has to be higher than the natural environment noise to hear, it is necessary to assume a higher risk of some damage to English listening.
As an ordinary office worker, bitmain l7 most of them are open office environment, if you do happen to be must focus on the work, congratulations, off work before high efficiency are going to be very low, because the whole day down, the company office of a variety of noise will not harm your English hearing, but will continue to cut off your ideas.
In fact, the noise in addition noise cancelling earbuds and earphones to harm English hearing, mood, reduce work efficiency, will continue to cause high blood pressure, cardiovascular disease, insomnia, psychological problems, etc., so a Ukrainian state enterprise even developed and designed a special production hat for the workers to block the noise.
Wear this hat, indeed blocked the noise, but the neck may also need to waste.
Defensive force noise, we do not need to put their own military into extraterrestrial beings, grateful for the rapid development of wireless Bluetooth headset, a pair of noise reduction wireless Bluetooth headset can be, more precisely, is noise reduction wireless Bluetooth headset.
Today, the existing noise reduction wireless Bluetooth headset on the market can be divided into three kinds: passive noise reduction wireless Bluetooth headset, voice call noise reduction wireless Bluetooth headset, noise reduction wireless Bluetooth headset.
Passive noise reduction is very easy to understand, from the physical aspects of the removal of noise management, in short, is the use of silicone rubber headphones immediately plugged inside the ear, so that certainly isolated part of the external sound, this type of noise reduction is more simple and direct, can not identify the noise and effective sound, immediately unified protection, and in order to better pursue the perfect better sound insulation and noise reduction of the actual effect, must block the ears to death, wear a long time It is very easy to swell and uncomfortable inside the ear.
Voice call noise reduction is picked up by the microphone, through the cell phone headset optimization algorithm to achieve the purpose of noise reduction, but only when the voice call can let others feel a certain amount of noise reduction actual effect, non-voice call situation can not be noise reduction.
The real "noise killer" is noise-canceling wireless Bluetooth headset, it is based on the cell phone headset embedded noise reduction processing chip and the front and back of the left and right feedback microphone to generate a noise reduction system software, the collection of cell phone headset external environmental noise acoustic frequency, and then cause a noise with the same external frequency, the phase difference between the opposite of the acoustic frequency, the noise in the combined off.