How Do Guitar Amplifiers Work?

Guitar amplifiers amplify the sound fed into it from thethe guitarist wants a heavy distortion akin to heavy
guitar and drive the guitar loudspeaker. The soundmetal rock sound. To get this type of sound, the input
waves generated by the guitar strings are convertedsignal is fed into the signal modulation stage where the
into minute electrical signal with the help of the guitarsignal undergoes the required (but controlled) distortion.
pick up and then fed into the guitar amplifier (or simplyThe same applies to other sound effects like
guitar amp). Depending on whether or not the input ofwah-wah sound, reverb etc. Many guitar amps have
the guitar amp can work with the minute signal comingequalizers and other tone control knobs, which also
from the guitar, the guitarist may need to feed thecome under the signal modulation stage.
guitar signal first into a pre-amplifier and then take theSignal Amplification Stage
output from the pre-amplifier to feed the guitar amp.The signal amplification stage is the 'business' stage of
The working of a guitar amp typically has four stagesany guitar amp. It is here where the guitar sound is
- input, signal modulation, signal amplification and thenactually amplified. Good guitar amps will faithfully
finally the output stage.magnify the signal coming from the Signal Modulation
Input StageStage, i.e. the incoming signal will be the exact replica
The input stage of the guitar amp accepts the inputof this stage's outgoing signal, only that it will be of
signal either from the guitar pre-amp or directly frommuch greater amplitude. It is the 'business' of any
the guitar itself. Normally, there are input female jacksamplifier (be it voice or guitar amp) to faithfully amplify
installed onto the amplifier where you attach the inputthe incoming signal.
signal cable. If the guitar signal is too weak to be fedOutput Stage
into the guitar amp, the signal should first pass throughThis is the final stage of all guitar amps. Some guitar
a guitar pre-amp. It is very important that there isamps have the output driver stage as a part of the
proper impedance matching between the availableoutput stage, while some of them do not. In some
input signal impedance and specified guitar amplifier'scheap guitar amps, the outgoing signal from the signal
input signal impedance. More often than not, signalamplification stage is directly fed into the loudspeaker.
impedance mismatch is the cause of deterioration ofHowever, good guitar amps have proper signal
the final guitar sound on the loudspeaker.conditioning output stage where it is ensured that
Nowadays, there are many guitar amps, which have aoutput signal is properly matched to the input
pre-amplification stage incorporated into them. For suchspecifications of the loudspeaker.
amps, you do not need to pass the guitar signal into aEvery good guitarist should have good knowledge
separate pre-amp. You can directly feed the signal intoabout guitar amps. Getting a good guitar amp is very
the amp itself.important if you wish to have a reliable and predictable
Signal Modulation Stageoutput musical sound whilst playing your guitar.
Plain in and plain out is not exactly the way normalFor more information and reviews on guitars, guitar
electric guitarist likes it. He wants the guitar sound to beamplifiers and equipment visit GuitarHeadz.com, the
jazzed up, twangy, funky, heavily distorted etc. etc. Forcomplete guide for anything you want to know about
such sounds, the input signal has to under goguitars and related gear.
modulation before they can be amplified. Say suppose