An electronic amplifier is a device for increasing the power of a signal. It does this by taking power from a power supply and shaping the output to match the input signal. This process invariably introduces some noise and distortion into the signal, and the process cannot be 100% efficient – amplifiers will always produce some waste heat.
Translation:
Italian: Amplificatore
German: Verstärker
Bulgarian: Yсилвател
Norwegian: Forsterker