In this blog we talk about audio amplifiers and I would like to get more detail information about them. An audio power amplifier is an electronic amplifier that amplifies low-power audio signals (signals composed primarily of frequencies between 20 - 20 000 Hz, the human range of hearing) to a level suitable for driving loudspeakers and is the final stage in a typical audio playback chain.
If we talk about the history of amplifiers, we can say, the audio amplifier was invented in 1909 by Lee De Forest when he invented the triode vacuum tube. The triode was a three terminal device with a control grid that can modulate the flow of electrons from the filament to the plate. The triode vacuum amplifier was used to make the first AM radio. Early audio power amplifiers were based on vacuum tubes (also known as valves), and some of these achieved notably high quality (e.g., theWilliamson amplifier of 1947-9). Most modern audio amplifiers are based on solid state devices (transistors such as BJTs, FETs andMOSFETs), but there are still some who prefer tube-based amplifiers, and the valve sound. Audio power amplifiers based on transistors became practical with the wide availability of inexpensive transistors in the late 1960s.
So, an electronic amplifier, or shortened amp is an electronic device that increases the power of a signal. So if you have a sound from a device and want the sound to be amplified, the amplifier is the device that can help you do this. Numerous types of electronic amplifiers are specialized to various applications. An amplifier can refer to anything from an electrical circuit that uses a single active component, to a complete system such as a packaged audio hi-fi amplifier.
Amplifier that any device is characterized by different specifications which actually should be taken when it is designed in consideration of them, and here are some highlights:
Noise
andwidth,
Gain,
Efficiency,
Linearity,
Output dynamic range,
Rise time, settling time, ringing and over shoot that characterize the step response
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| Generic Amplifier |
