Because when people speak into the microphone, the output power of the microphone is too small to transmit, so the power should be amplified. Microphone amplifier converts a very weak sound signal into an electrical signal and amplifies it, so that the machine can better identify the useful signal, and finally drives the amplifier to drive the speaker to make sound.
2. Adjusting the volume is to control its output power. It's just a potentiometer, which can't amplify. It's used for control. Software is also used for control. The amplifier is a triode.
3. Any circuit will lose sound, and noise reduction is only one of the circuits, not all.
Extended data:
The earliest and most important function of voice amplifier is to amplify the sound of microphone. Later, the integrated voice amplifier integrated some simple functions such as filtering and recording into one device.
When an independent microphone is used and there are certain requirements for recording quality, or the signal strength of the microphone is not enough, voice playback becomes an essential device.
The basic structure of microphone amplifier is voltage limiter, equalizer, flutter eliminator, hiss eliminator, noise gate and so on.
There is also an independent voice amplifier, which is only responsible for amplifying the microphone signal and doing some necessary processing, and then turning it into a line output signal for transmission.
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