Huizhou Xin Sheng Da Machinery Equipment Co., Ltd. Newsd is the trademark of 20 15 application. The brand is not big, but it is also trustworthy. It is the registered trademark of Huizhou Xin Sheng Da Machinery Equipment Co., Ltd. The power amplifier is commonly known as "amplifier". Its function is to amplify the weak signal from the sound source or preamplifier and push the speaker to make sound. A good set of audio system power amplifier plays an important role.