Music is just... functional.
It is a CREATION by GOD Himself, and is based in nature.
There is a series of notes called the Overtone Series that happens when a sound is struck, whether that be a knock on wood, metal, or the pluck of a harp string.
The root tones are further apart in the bass, and repeat often within the 1st octave. The 2nd octave adds more complex notes like the 3rd and the b7th. The 4th octave is full of more complex notes.
When even one string is struck on stringing instrument to produce one musical note, that string is actually vibrating ALL... of those notes on the Overtone Series at the same time. What we actually hear is NOT just one single tone, but an amalgamation of all those Overtone Series tones joined together. It simply sounds like one note. Like the note A-440, it vibrates at 440 cycles per second, along with the Overtone Series tones around it.
EACH musical note also has a COLOR FREQUENCY that can be associated with it.
Did GOD create 'color' also? Yes He did!
Each color vibrates at a specific frequency also, which establishes whether it is red, blue, yellow, green, or some other color. There has been much research in the past and even instruments created that joins musical notes with showing their respective color. (see color and music therapy).
What KIND of sound is produced by a musical instrument simply falls within the spectrum of God's creation. Just as there is also sadness, anger, i.e., the full range of emotions in this world, which GOD also created, so likewise music can be written that serves all of them.
Like the orchestra composer Gustav Holst and his composition
Mars. He wrote that piece to express Mars, the god of war. Did Holst accomplish that emotion? And does that make that music itself evil? No, it's the 'theme' intended that creates the emotion to express the evil god of war Mars. The music written to accomplish it and produce the emotion isn't evil, but is just functional. And I'm sure Holst had no intention to write 'evil' music. He simply wrote a piece of music to represent each of the 7 planets, and symbolic representations dealing with each one.