Okay, I have some info to add here, and some info to ask here.
I have thought on this for quite some time, And I have searched, I cannot find much on this subject, So please excuse the lesser resources. I will be mentioning anime, books etc. because that's how I think. I connect what I do not know with what I do know .
As I understand, Sound by itself alone is very powerful, We can shatter glass at a certain pitch and volume, ( Body's and cars too if you raise it high enough ) It can travel very fast, ( not at lightspeed but pretty darn fast ).
In the Inheritance Cycle books, Eragon asks his mentor, why they have to speak their spells if they can cast through thought alone. His mentor replies that while this is true, you do not need sound to make your spell, its much harder, as our thoughts go very fast and often jump from one thing to another, ( You would have to have complete focus to do it, any stray thought could cause your spell to blow up in your face. ) Speaking the spell makes it easier to direct and control.
Music, makes the magick more powerful, as you are not only singing your spell, but adding energy to it, to make it stronger, this is why in some cases of fiction spell casters sing. However, you can add energy to it through instruments and not singing. The more fast pace and moving the music is, the more likely powerful your spell will be.
Am I correct or close to it? Like I said I have not been able to find much about music/sound and what it affects pertaining to magick, I am unsure and am asking for help.