Introduction
A stereo receiver is actually three individual devices manufactured in one, clean box. Therefore, the stereo receiver handles a lot of the responsibilities of the stereo system, including switching between components, receiving the audio signal, amplifying the audio to a level that can power the speakers and handling basic controls like volume, balance and programming.
Inputs
The first responsibility of the home stereo receiver is to receive the audio signal from an input source such as a CD player, MP3 player or television. There are many inputs in the back so that you connect all of your sources. You can then use the receiver to select which source that you want to use and switch between sources. When you begin playing your audio source, it sends an audio signal to the stereo receiver's preamplifier section. The preamplifier decodes the signal, and based upon what format that it's sent in, breaks the signal into individual channels to be routed to each speaker. The preamplifier also handles audio controls like volume and balance. The preamplifier powers the signal slightly and then when it has finished processing the signal it sends it to the amplifier.
Amplification
The stereo receiver's amplifier has a more simple, one-dimensional role. It is responsible for taking a line level signal and adding power to it. Speakers need significantly more power than a line level input would provide, so the amplifier adds the power while maintaining the proper frequency and audio characteristics of the original signal. A more powerful version of signal that maintains the integrity of its audio characteristics is created and then sent to the speakers.
Radio
The third piece of the stereo receiver is a built-in radio tuner. When an antenna is attached to the receiver, the tuner allows you to receive radio broadcasts and switch between stations.
Tags: stereo receiver, audio signal, audio characteristics, controls like, controls like volume