Evolutionary Psychology of Why Do We Enjoy Music

"Dr John Powell, a Visiting Professor of Materials Science at the University of Nottingham said: 

The sounds of music are not the same as noises. Your ears are there to make sure you stay alive: they're a warning system, designed to analyse sounds for danger. But we can quickly recognise that a musical instrument is unlikely to be lethal. When you hear music, your ear drum moves in and out in a regular, repeated way, many times a second. We recognise that it's not dangerous, so we can focus on the harmonies and tunes – and enjoy them."

Moreover, we don't enjoy bad music, we enjoy the music that has a repetitive rhythm in it, as we listen to it we wait for that rhythm to arrive again, and just as it does we have feelings of accomplishment. Depending upon our culture and habits we like different types of music. It's also manifestation of human urge of pleasure, that sometimes we find in paintings, art, and religion. A soothing or good music gives us feeling of being in safe zone. Turning to religion make us feel protective. It's interesting to note that we turn to music or religion more often when we are in an unusual state of mind. Sometimes in stress, sometimes in happiness. It's human escape or sometimes celebration.
We also use music or musical voice to express our strong emotions or ideas, or just incite or motivate others in different ways in the form of anthem, a war song, or a sad song. A musical note is easy to remember and it shows correlation of things you said in the form of poetry that also repeat itself like musical instruments. We the humans figured it out long ago that a poetic notion is easy to transfer and remember for longer period of time than a normal statement.