The noise canceling of bluetooth earphones which uses some of the methods to reduce noise; at present day, there are two types of noise canceling bluetooth earphones which are active noise canceling and passive noise canceling
Classification introduction
The active noise cancelling function is to generate a reverse sound wave equal to the external noise through the noise reduction system, neutralize the noise, and achieve the effect of noise reduction and active noise canceling bluetooth earphones with noise-reducing circuits that compete with external noise.
Most of them use a large head-mounted design, which can be used to block external noise by using earplugs and bluetooth earphones casings, for the first round of sound insulation, and also for there is plenty of room to install active noise reduction circuits and power supplies
The passive noise canceling bluetooth earphone mainly forms an enclosed space by surrounding the ear or uses a soundproof material such as a silicone earplug to block external noise. Since the noise is not processed by the noise reduction circuit chip, generally only the high-frequency noise is blocked, and the noise reduction effect on the low-frequency noise is not obvious
Applicable Principle
The three noise reduction measures commonly used to reduce noise, namely noise reduction at the sound source, noise reduction during propagation, and noise reduction at the human ear, are passive. In order to proactively eliminate noise, the technology of "active noise reduction" was invented.
Its principle is: all the sounds heard are sound waves, and they all have a certain spectrum. If an acoustic wave can be found, its spectrum is equal to the amplitude of the noise to be cancelling, and the phase is just the opposite (180° difference), and the superposition of the two can completely cancel the noise. The key is how to get the sound that cancels the noise.
The actual method is to start with the noise itself, monitor the noise with a microphone, and then try to generate a reverse sound wave through the electronic circuit and play it through the speaker.
People of Applicable
The first is business people. Due to frequent business trips, especially those who travel between different cities every day, they must hate the noise in the cabin. If there is a noise-cancelling bluetooth earphone neckband, they must be able to stay away from these noises and relax by listening to music
Second, The office workers who crowded the subway every day are already familiar with the noise in the subway. However, if there is a noise-cancelling bluetooth earphone at this time, not only can it be far away from the noise, but also can adjust the mood through headphones, enjoy this happy while traveling
Office workers also need a pair of noise canceling headphones. Sometimes when thinking about planning, listening to the sound of central air conditioning is particularly upset, and if there are colleagues around at this time, it is even more annoying. At this time, you may wear a pair of noise-cancelling neck bluetooth earphones to expand your thinking in beautiful music