GUITARAMPLIFIER
Guitar amplifier
A guitar amplifier is an electronic amplifier designed to amplify the electrical signal of an electric or acoustic guitar so that it will produce sound through a loudspeaker. Most guitar amplifiers can also modify the instrument's tone by emphasizing or de-emphasizing certain frequencies and adding electronic effects, typically distortion and reverb. For acoustic guitar, vibrations of the strings are "picked up" by a microphone or piezoelectric pickup. For electric guitars, strings are all made of metal, and the pickup works by electro-magnetic induction.The above text is a snippet from Wikipedia: Guitar amplifier
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