850 power amplifier, standard voltage AC dual-channel 18V, equipped with 8Ω speaker, each channel has undistorted output power of 20W, and the maximum power is 25~30W. It is recommended to use 100W transformer, and 50~80W transformer is barely enough. The heat sink of the board is a little small.

Power amplifier, referred to as power amplifier, generally refers to one of the most basic devices in audio system, commonly known as "amplifier". Its task is to amplify the weak electrical signal from the signal source (from the mixer in the professional sound system) and drive the speaker to make sound.