What principle do Noise cancelling headphones use? - oem factory

What are the active noise cancelling of the oem noise cancelling headphones factory?

oem noise cancelling headphones factory said earlier that there are three noise reduction methods currently used in Bluetooth headphones, and they also mentioned that active noise reduction will lead the trend of Bluetooth headphones, so what is the specific principle of active noise reduction? How many solutions or methods are there? Today, what are the active noise canceling of   oem noise cancelling headphones factory?

At present, the main active noise reduction functions of oem noise cancelling headphones factory are roughly divided into four types, namely ANC, ENC, CVC, DSP and other noise reduction technologies

Noise reduction headphones, using ANC noise reduction and active noise control, are mainly aimed at high and low frequency noise in the external environment. They are different from the passive sound insulation of general headphones. The principle is:

1. First detect the low-frequency noise (100 ~ 1000Hz) in the environment that the ear can hear by the signal microphone installed in the headphones (currently it can reach 3000Hz)

2. Then the noise signal is transmitted to the control circuit, and the control circuit performs real-time calculations

3. Through the Hi-Fi speaker, a sound wave with the opposite phase and the same amplitude of the noise is emitted and added to the external noise to cancel the noise

4. So the noise disappears and is inaudible

Active noise canceling is divided into feedforward active noise canceling and feedback active noise canceling according to the position of the pickup microphone.

In this way, this headphones needs a period of algorithm processing time, first learning the noise, this learning needs time, and then the phase of the learned noise is reversed, and there is an adaptive adjustment period.

Active noise-canceling headphones are expensive, but they are generally effective and comfortable to wear. But it needs independent battery power supply, most passive noise canceling headphones can be used without power consumption (nor active noise canceling)

ENC noise canceling

ENC (Environmental Noise Cancellation, environmental noise cancelingtechnology), can effectively suppress 90% of the reverse environmental noise, thereby reducing the environmental noise up to 35dB or more, allowing gamers to communicate more freely. Through the dual-microphone array, it accurately calculates the direction of the caller's speech, which protects the target voice in the main direction while removing various interference noises in the environment.

DSP noise canceling

DSP is an abbreviation for English (digital signal processing). Mainly for high and low frequency noise. The working principle is that the microphone collects the external environment noise, and then the system replicates a reverse sound wave equal to the external environment noise to cancel the noise, so as to achieve a better noise canceling effect. The principle of DSP noise canceling is similar to ANC noise canceling. However, the forward and reverse noise of DSP noise canceling directly neutralizes and cancels each other within the system.

CVC noise canceling

CVC (Clear Voice Capture) is a noise canceling technology for call software. Mainly for the echo generated during the conversation. Through the full-duplex microphone noise cancellation software, it provides the echo and environmental noise cancellation function of the call. It is the most advanced noise canceling technology in the current Bluetooth call headphones.

The main reason why oem noise cancelling headphones factory predict that Bluetooth headsets will lead the trend with active noise reduction in the future is that the upstream R&D companies of oem Bluetooth headset manufacturers, especially chip companies, plan companies to provide active noise reduction solutions, and even tenwin is now Research in the direction of active noise reduction. Although there is no relevant data support, oem Bluetooth headset manufacturers can judge from the actions of upstream companies that active noise reduction will be the mainstream of the Bluetooth headset industry.