Tonal quality can be changed by moving the mike towards lower or higher strings. An alternative is to use a PZM microphone attached to the inside of the Piano lid or possibly attached to the bottom. If you are in a hurry, you can even place a PZM on the floor under the piano. Since the wood of the Piano tends to direct sound from the speakers back to the microphone, feedback may be a problem. An upright Piano can be miked with a PZM inside the lid or a mike on a boom stand behind the Piano.
Tonal quality varies greatly with mike placement.
Condensor microphones are one example. If the mixer has Phantom Power, it usually has a switch to turn it on or off. Be sure the Phantom Power switch is turned off if you are not using microphones that need it. Occasionally getting close for effect adds variety. As mentioned above, the distance the sound source is from the microphone is very important.