Amplifier, itsll name is the power amplifier. As the name suggests, amplifier is to amplify the power. The power amplifier belongs to the post stage amplifier, and its function is to enlarge the signal sent by the front stage processing equipment to large enough (the final frequency of the signal is in accordance with the frequency of the power amplifier, for example, 100W's amplifier can reach 28V with 8 European load) to drive the sound box. Amplifier is the "power amplifier" for short, the output signal amplitude and the intensity of the signal source (such as the CD/DVD/ card holder radio head, mp3 and so on) is not enough to drive high power loudspeaker (sound box horn), so it must be amplified by the amplifier.
The mixer, as the name suggests, is used for tuning. The mixer belongs to the front stage processing equipment, and it usually does not have a built-in amplifier. Its function is to enlarge the multi-road sound source (such as record machine, CD machine, microphone and so on) through the front stage and carry out simple tone processing. The number of roads can be divided into 6 road, 8 Road, 16 Road, 32 road and so on. Its main role is to facilitate users to manage multi-road sound sources.
Mixer digital amplifier
and digital public address amplifier are two different concepts. The power of the audio signal is very small and can not drive a large speaker directly (such as the loudspeakers in the street). So if you want to drive those speakers, you’ll need a power amplifier. The power amplifier can amplify the current of the audio signals and the voltage to enlarge the power (P=UI).
But the mixer is not used to amplify the power and drive the big speakers and big horns, but to adjust the tone, such as adjusting the high pitch, the bass and the middle tone of a song, the singer's voice and the accompaniment of the musical instrument, making the singer's singing and musical accompaniment sound more pleasant to hear and more harmonious.
As we need multi-road signal sources (such as there are more than one microphones) to adjust the complexity in some professional occasions, a DJ is needed to control them at any time. The scheduling device for this complex signal source is the "mixer". The household occasions are not so complex, so their functions are integrated into the power amplifier. It is very important to separate the power amplifier from the front and post stages. The front stage is responsible for some functions of the mixer, and the "pre-amplification".
In short, power amplifier is the thing that can let the people at the most back of the big concert or can not get close to the stage and the speakers hear the singing of the singers, and the mixer is the thing that can make the singing more pleasant to hear.