助聽器是一種放大，做為聽力輔助的電子器材，其基本構造是麥克風、放大器、耳機(喇叭)、電源和電池構成。隨著科技的進步，助聽器在聲音訊號處理部份由最基本的類比演進到數位，而方向性麥克風也成為基本的配備之一。數位助聽器的優點為噪音及回饋音消除，這些技術使得使用者在不同環境下可以獲得良好的聲音品質，也可藉由不同的頻段調整而讓不同使用者獲得最佳的使用體驗。

Hearing aid is a kind of amplification, as hearing aids electronic equipment. The basic structure is microphone、amplifier、headphones (speakers)、power supply and battery composition. With the development of science and technology, hearing aids in the audio signal processing part of the evolution from the most basic analog to digital and directional microphone as one of the basic equipments. The advantages of digital hearing aids are noise reduction and feedback reduction, which allows users to achieve good sound quality in different environments. Also, to adjust different frequency bands for different users to get the best experience.

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