The power amplifier is commonly known as the "amplifier". Its function is to amplify the weak signal from the audio source or preamplifier and push the speaker to play sound. A good sound system amplifier plays an important role. Power amplifiers can generally be divided into three categories: "professional power amplifiers", "civilian power amplifiers" and "special power amplifiers".

DENON (Japanese brand in 1910, world brand, top ten power amplifier brands); YAMAHA (founded in Japan in 1887, top ten power amplifier brands); ONKYO (Japanese brand, audio and video field A leading brand for more than half a century, one of the top ten power amplifier brands); Marantz (a high-end power amplifier brand under Philips, one of the top ten power amplifier brands in the United States in 1953); SONY (a world brand in Japan, one of the top ten power amplifier brands in 1946) Brands; SANSUI (a world-famous speaker brand in Japan in 1944, one of the top ten power amplifier brands); Pioneer (a world-famous speaker brand in Japan in 1938, one of the top ten power amplifier brands); Tianyi (a famous brand, Guangzhou Tianyi Electronics Co., Ltd. company, one of the top ten power amplifier brands); Harman Kardon (a famous American audio equipment brand, one of the top ten power amplifier brands); QiSheng (a well-known trademark in China, Dongguan QiSheng Electronics Industrial Co., Ltd.)

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