For me, classical music is Ni, because it's so abstract, and produces imagery in your mind. The tone of music affects your inner impressions and the mental images in your head because of it are nothing directly related to the objective world.
Same goes for any foreign language music, where you cannot understand the words. And since you can't understand them, your subjective interpretation will more likely be of things completely unrelated.
Certain tones of music make you think of flowers and gardens, other tones make you think of demons and monsters.