A power amplifier is a power amplifier, which is used to amplify the power and push the speakers to show more sound details. If the playback device is directly connected to the speaker, it may be impossible to push the speaker. This is like a person who has practiced his throat, and his voice is full of breath and very pleasant. This is because after professional training, he knows how to use the vocal parts to make a good sound. And a person who has not practiced his voice, singing is easy to go out of tune and it is not good to listen to. If your speaker is an active speaker, it has a built-in power amplifier, which can give a certain impetus when the sound source is input. If it is a passive speaker, there is no power amplifier and no sound can be produced, but when you match a different power amplifier , It will bring you different sound effects, this one is more playable. In short, different speakers and different power amplifiers, after matching, will have different sound effects, and these effects may even vary greatly from time to time. If you listen a lot, you can naturally find your favorite style.