Guitar Amplifiers
A guitar amplifier (or guitar amp) is an electronic amplifier designed to make the signal of an electric or acoustic guitar louder so that it will produce sound through a loudspeaker and modify the tone by emphasizing or de-emphasizing certain frequencies and adding electronic effects.
The amplifier comprises a preamplifier stage, which amplifies the voltage of the signal from the guitar, and a power amplifier stage which delivers a higher current to the speaker to produce sound. The preamplifier stage may also have electronic effects such as distortion, chorus, or reverb and additional controls such as a graphic equalizer. Amplifiers may use tubes (or valves), or solid state (transistor) devices, or a mixture of both.
There are two configurations of guitar amplifiers: combination (“combo”) amplifiers, which include an amplifier and one, two, or four speakers in a wooden cabinet; and the standalone amplifier (often called a “head” or “amp head”), which does not include a speaker. Guitar amplifiers range in price and quality from small, low-powered practice amplifiers, designed for students, which sell for less than US$50, to expensive “boutique” amplifiers which are custom-made for professional musicians and can cost thousands of dollars.
