Editing Instrument amplifier (section)

{{Short description|Amplifier with loudspeaker for use with musical instruments}}
{{about|amplifiers for musical instruments|amplifiers for test and measurement|instrumentation amplifier}}
{{refimprove|date=July 2007}}
{{Use American English|date=September 2024}}

[[Image:Pink-Guitar-Amp.jpg|thumb|right|300px|A Fender ''combo'' amplifier. The combination amplifier is a preamplifier, power amplifier and tone controls and one or more loudspeakers or drivers mounted in a portable wooden cabinet. This amp's sound is being picked up with a microphone in a recording studio.]]

An '''instrument amplifier''' is an [[electronic amplifier]] that converts the often barely audible or purely electronic signal of a [[musical instrument]] into a larger electronic signal to feed to a loudspeaker. An instrument amplifier is used with musical instruments such as an [[electric guitar]], an [[bass guitar|electric bass]], [[Hammond organ|electric organ]], [[electric piano]], [[synthesizer]]s and [[drum machine]] to convert the signal from the [[pickup (music technology)|pickup]] (with guitars and other string instruments and some keyboards) or other sound source (e.g, a synthesizer's signal) into an electronic signal that has enough power, produced by a [[power amplifier]], to drive one or more [[loudspeaker]] that can be heard by the performers and audience. 

Combination (combo) amplifiers include a [[preamplifier]], a power amplifier, tone controls, and one or more speakers in a [[speaker enclosure|cabinet]], a housing or box usually made of wood. Instrument amplifiers for some instruments are also available without an internal speaker; these amplifiers, called ''heads'', must plug into one or more separate speaker cabinets. Instrument amplifiers also have features that let the performer modify the signal's [[Timbre|tone]], such as changing the equalization (adjusting bass and treble tone) or adding [[effects unit|electronic effects]] such as intentional [[distortion (music)|distortion or overdrive]], [[reverb]] or [[chorus effect]].

Instrument amplifiers are available for specific instruments, including the [[guitar amp|electric guitar]], [[bass amp|electric bass]], [[keyboard amp|electric and electronic keyboards]], and acoustic instruments such as the mandolin and banjo. Some amplifiers are designed for specific styles of music, such as the [[Fender tweed]] guitar amplifiers, such as the [[Fender Bassman]] used by [[blues]] and [[country music]] musicians, and the [[Marshall amplifier]]s used by hard rock and heavy metal bands.

Unlike [[AV receiver|home hi-fi amplifiers]] or [[public Address system]]s, which are designed to accurately reproduce the source sound signals with as little distortion as possible, instrument amplifiers are often designed to add additional tonal coloration to the original signal, and in many cases intentionally add some degree of [[distortion (music)|distortion]].