Acoustic amplifiers
Think of acoustic amplifiers as small PA systems. They are designed to amplify a clean signal, and do not change the tone of the instrument.
Keyboard amplifier
Many keyboard amplifiers act as acoustic amplifiers and vice versa, as keyboardists want a clean tone from their instruments.
Electric Guitar Ampere
Electric guitar amplifiers are designed to color the sound of the guitar. The tone of a Fender amplifier sounds significantly different than a Marshall or a Mesa Boogie. In that sense, they are part of the signal chain, so electric guitarists choose their amplifiers based on the sound they want.
Electrical office technology
Although solid state circuits have evolved considerably, most electric guitars opt for tube amplifiers to get a smooth ‘creamy’ distortion from their amplifiers. Solid state electric guitar amps are often much cheaper than electric guitar amps.
Other options
Because acoustic players strive for openness above all, many eschews disappear completely and either use a microphone on the instrument to get a true natural sound, or connect the instrument to a PA via a direct in (DI) box. Many modern acoustic instruments have a mixed option that mixes a small microphone for natural sound with a pickup for sound amplification. These systems require a special preamp. Some rock guitarists, who want to add an acoustic guitar sound to their live repertoire, try to connect their acoustic to their electric amplifier, only to find that the sound is wrong. An electric guitar amplifier differs significantly from an acoustic amplifier.
Source:danspela.com