Hi, an amplifier is best thought of a s 'modulated power supply'.
The word 'amplifier' is a bit misleading because it is often thought that it makes the initial signal 'bigger', when what is happening is the signal is used to modulate the main power supply which drives the loudspeakers.
There's no way the small electronic signal produced by the interaction of guitar strings with the magnetic pickup heads has enough muscle to move the loudspeaker drivers, so a DC power supply with the capacity to produce lots of current, enough to move the loudspeaker cones, move air and hence make a lot of sound, is used.
Of course, if a DC power supply is simply connected to a loudspeaker, apart from the initial movement of the cone, nothing else happens because the power going through the loudspeaker, from the DC source, is not changing.
So, if the DC power supply, (its voltage/current) is made to change in line with the varying signal from the guitar pickups, then we get a representation, a copy, of that original 'source' electrical signal produced via the the loudspeaker.
The tubes and transistors used in various amplifier design act like 'electronic levers' - they control the changes in the voltage(es) that are supplied by the power supply.
The job to modulate that DC supply, belongs to the amplifier.
The better the quality of that power supply, the better the amplifier is.
The word 'amplifier' is a bit misleading because it is often thought that it makes the initial signal 'bigger', when what is happening is the signal is used to modulate the main power supply which drives the loudspeakers.
There's no way the small electronic signal produced by the interaction of guitar strings with the magnetic pickup heads has enough muscle to move the loudspeaker drivers, so a DC power supply with the capacity to produce lots of current, enough to move the loudspeaker cones, move air and hence make a lot of sound, is used.
Of course, if a DC power supply is simply connected to a loudspeaker, apart from the initial movement of the cone, nothing else happens because the power going through the loudspeaker, from the DC source, is not changing.
So, if the DC power supply, (its voltage/current) is made to change in line with the varying signal from the guitar pickups, then we get a representation, a copy, of that original 'source' electrical signal produced via the the loudspeaker.
The tubes and transistors used in various amplifier design act like 'electronic levers' - they control the changes in the voltage(es) that are supplied by the power supply.
The job to modulate that DC supply, belongs to the amplifier.
The better the quality of that power supply, the better the amplifier is.