The core of the HiFi amplifier system is responsible for amplifying the signal received from the cd section, transmitting it to the speakers and then emitting sound.
Amplifiers are also divided into pre-stage and post-stage.
(1) the main function of the pre-stage is first of all the volume control, followed by the received voltage amplification, because most of the cd player even with volume adjustment, but the output voltage is insufficient, and finally there is a choice of adjusting the input source.
(2) the function of the rear stage is power amplification, simply put, is to amplify the current, the audio source signal to the speaker playback (Note: no amplifier power the higher the better, the first is to see the parameters match, and then look at the system with the last to achieve the best results)
1. How to choose ClassA and ClassAB?