Amplifiers

Amplifiers.

Just as the name suggests, they make sound louder but they also do much more than that.

Not many amplifiers will simply make things louder they will also color that sound to some extent.
Domestic Hi-Fi is a prime example of doing this. A classical music lover would appreciate orchestral music not being tampered with tonally. It needs to be as faithful as it can be to a live performance. The dynamics of a full symphony orchestra is far more subtle than most popular music today.
An amplifier for this purpose needs to be more linear or flat in its response with little coloration.
Electric guitar amplifiers on the other hand, are designed to have very different responses from one another. Fender Vox and Marshall amps for example, all produce distinctive guitar sounds. It is not just the guitar but also the amp that complements it.
Acoustic instrument amplifiers on the other hand need to be a little more faithful in their reproduction.
Nowadays there are specific amplifiers designed for this purpose and they offer more complex EQ contols to shape the desired sound of the players instrument.
There is a myriad of acoustic pickups available today for a wide range of instruments.
They too “color” the natural sound and the role of an acoustic amp is to correct that coloration if required.
Piezo crystal pickups tend to exaggerate particular frequencies on acoustic instruments and this needs to be dealt with via good quality equalization.
The reality is once you plug an acoustic instrument into a PA or amplifier it becomes and electrified instrument and all the same rules apply.
So learning about EQ will help enormously to achieve the sound you are searching for.