Active Noise Canceling Headphones

Abstract

The invention discloses an active noise reduction earphone, which comprises a casing, the front end of the casing has a sound hole, and a feedback microphone for picking up ambient sound, a low-frequency speaker unit, a mid-high frequency speaker unit and a noise reduction circuit are arranged in the casing. The microphone is only electrically connected to the low frequency speaker unit through the noise reduction circuit. Applying the active noise reduction earphone provided by the present invention, the feedback microphone collects the environmental noise inside the earphone and outputs a signal with the same amplitude and opposite phase as the environmental noise to the low-frequency speaker unit through the processing of the noise reduction circuit. Low, high-frequency cut-off frequency is low, so the high-frequency anti-phase sound waves emitted by the low-frequency speaker unit are attenuated, and the high-frequency amplitude is physically reduced while achieving noise reduction. There is no need to adjust the filter to reduce the high-frequency amplitude, and the high-frequency howling is avoided in a physical way.

Description

technical field [0001] The invention relates to the technical field of earphones, and more specifically, relates to an active noise reduction earphone. Background technique [0002] In recent years, active noise-canceling headphones have been highly praised to meet people's needs for listening to music quietly. The noise reduction methods of active noise reduction headphones can usually be divided into analog noise reduction and digital noise reduction. Through the design of the filter, a signal with equal amplitude and opposite phase to the external noise is generated to achieve the noise reduction effect. Common types of noise reduction include feed-forward noise reduction, feedback noise reduction and hybrid noise reduction, which are widely used in headsets, earbuds, and in-ear headphones. However, the design of the filter is restrained by the phase and the amplitude, and it is easy to cause high-frequency howling in the feedback noise reduction, which affects the use. ...

AI Technical Summary

Problems solved by technology

However, the design of the filter is constrained by both phase and amplitude. Feedback noise reduction is likely to cause high-frequency howling, which affects the use.

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