Music obvious has an effect on one's experience. There seem to be close relationships between forms of music and mental states, such as emotions. This kind of stuff is everywhere. Here are some examples.
Songs in a minor key often evoke melancholy, whereas songs in a major key evoke happiness.
The tempo of a song is also associated with mood. You never hear fast funeral dirges.
Sounds coming from different instruments have different effects. Compare the sound of a flute with the sound of an electric guitar playing through a highly distorted amplifier. They could play the same melody, but achieve vastly different effects on one's mental states.
Everything about music has this potential effect. The volume, tempo, rhythm, pitch, harmony, timbre, instrumentation, etc. Anything about a particular song can contribute to producing a certain mental state.
That's the power of music. That's why you have film scores and soundtracks.
Here's a question. What do we make of the fact that music has this causal effect on our mental states? Why does music have this effect? Why did our brains evolve to be sensitive to these musical details? Do certain aspects of music have the same effects on individuals across time and culture? If so, why? If not, where do these associations come from? Suppose that the association of minor keys with sadness is a western European thing. Then how did that association come about?