Hey Van2006.
Whether you use a pickup, a piezo transducer or a microphone; you will get the best results if you use a preamp or a Direct Injection Box. (DI)

After the signal has been regulated in the preamp or DI you can choose to take it to your guitar amp or mixer.

Remember that modern mixers and interfaces have built in preamps capable of regulating the signal and give you the needed output level.

The majority of recording studios use high quality microphones connected to preamps to capture the sound of the acoustic guitars.

The placement of the microphone, piezo or pickup has a direct impact on the tone of your guitar, giving you sometimes too much treble or too much bass.

Finally, you can further shape the sound of your guitar by adjusting the lows, mids, highs and presence knobs on your amp or using an equalizer.

Hope that helps. :)