You can find amplifiers almost in every electronic devices all around us, you can find it in televisions, computers, portable CD player and any other device that have speakers to make sounds.
Now learn how amplifiers gives power to your speaker.
Electronic sound equipment represent sound as a varying electric current, first the sound waves move a microphone diaphragm back and forth, then the microphone turn this movement into an electrical signal, and the electrical signal fluctuates to represent the compressions and rarefactions of the sound wave. Then a recorder encodes this signal as a pattern. And then a player like the tape deck re-interprets this pattern as an electrical signal and make the speaker’s cone move back and forth, this will re-creates the air-pressure movements that recorded by the microphone.
All of the above device are essentially translators, they turn a signal into another form, and then getting it back to its original physical sound wave form.
But some of this re-created sound wave don’t have enough power to make the speaker cone move back and forth to create the sound again, so this is where an amplifiers do the job, it boost the audio signal so it will have a larger current while in the same time preserving the same pattern of change fluctuation.
