Data would hear noise assembled to make a flowing motion of sound where as a human would hear a beautiful medley of enchanting sounds, not individual noises but a whole living creature. Therefore, Data would never know what the actual quality of music would be to a human since he can not feel it or have the understanding of what it is like to have music change ones mood and talk to the person who is listening to it. .
Noetic Quality is another character that is often associated with the idea of mysticism. Inside the depths of this topic, a person who has experienced this have mind altering, mood changing developments all of a sudden. They happen in an instance but deliver great insights as to one's perception on life or events that have been happening. Think of an abusive father beating his children all their lives. Then when he is retired and sitting alone in his house, he sees a commercial on television of a happy family and realizes how horrible of a father he has been, but it took him his whole life to realize it in once instant. .
Imagine a mother speeding down the road with her three year old daughter next to her buckled the passenger seat. For the last several years the mother speeds everywhere she goes many miles over the speed limit. Then one day she is driving and watches a car wreck happen in front of her where a little child is killed by being thrown from the passenger seat due to the driver speeding. The mother that witnessed the accident would experience a Noetic Quality if she realized how speeding could not only endanger her, but also her child. It is a deep thinking, lost in ones own thoughts, type of mysticism that can't really be explained to another person, but insight as to how you are living your life and how it must change. .
Just these two states alone is what gives most people the idea of mysticism and insight into one own person's soul and better understanding of religion and the world around us, but there are also two more mystical states which are not so closely defined as the states mentioned before.