I have a very undeveloped idea of these very musically oriented people, but I have not placed them in any particular region or time in my world. I'm not even sure if I will put them in my current project...
Anyway, the idea started as many of my ideas start. I pictured a story...

The sound of wood crackling was mix with the smells of the first meal of the day. A captain exited his tent and began making rounds through the camp. The sound of armor rattled on every body that stood to attention as he passed. Small bags could be seen under the eyes of the men. They had been ordered to never to remove their armor and a shield rested nearby every man. It is hard to sleep fully clad in armor, but the orders were clear, and were obeyed.
The camp sat on the edge of a dry forest. A thick fog had rolled in just before dawn and was growing in the camp. With it grew an eerie silence. No one spoke as they cooked their morning meals and stretched their stiff bodies. Just mist and silence floated between the men as they ate and awaited orders.
The captain was the first to hear the sound. It was as the plucking of a harp far in the distance. He turned his head toward the shrouded field from whence the noise came. A stranger sound followed. It was as if heavenly voices floated through the fog. The sound grew louder and louder, and other men stood and lifted their faces to listen. Suddenly the camp was riddled with the cries of injured men as the voices fell from the sky in the form of arrows. The camp was suddenly covered in the strange weapons and the men were thrown into panic.
"Shields! Raise your shields!" The captain shouted over the sound of another incoming wave of arrow fire. The men that could quickly gathered themselves around the captain. The captain made hast with his band into the forest calling to the men as they went, "Make for the forest! We'll draw them in where we can see them!" The voices of the arrows dived into the now deserted camp behind them. Once they were safely below ample foliage the captain cried out, "Hold! We will hold them here!"
The men gathered themselves into a protective formation among the thickest portion of trees around. The sound of drums filled the forest, and they were soon accompanied by the sound of other instruments and voices which all played a battle song. The song seemed to herald the death of the small band huddled among the trees. It filled their hearts with dread.
"Courage men," said the captain in a steady voice. The drums seemed to cease, and there was silence once more. Every man's head searched left and right for the sight or sound of their enemy. Many of the men were breathing heavy, nervous breaths.
The drums began again, much faster than before. There was the cry of a mighty chorus, and the sound of many strange and terrible instruments. Soon the sounds had a visible source. From three sides, men clad in strange armor, wielding weapons which aided them in their battle song, came charging at the captain and his band. The captain quickly ordered his men to retreat in the one open direction left to them.
"Now turn!" he shouted suddenly. The men turned just as the flood of enemy soldiers came crashing against them. Every clang of the sword, every cry of the enemy only seemed to add to their great and terrible song. Some even held back and seemed to 'play' their swords and other weapons in great sweeps which created melodies among the cries of battle and the deaths of his men. The captain could not stop listening to the battle. It was all so masterfully conducted, like a song....
Soon the captain stood alone, utterly defeated. He was taken prisoner. Everywhere men were gathering the arrows which had cut his army into a third of what it was before the battle even began. As he was lead through his own camp he heard the songs of the enemy, though the melodies were scattered and each was driven by a separate emotion. Some were distant and full of grief while others were more joyous and full of laughter. The captain couldn't help but find comfort in the songs of grief. He passed by one who played an arrow as if it were a flute, and another who waved his sword through the air angrily but skilfully concocting a song over the body of a fallen soldier, and many others sat singing.

So anyway, that is the story which birthed these unnamed people. They basically form their whole lives around music. Even their battles are a carefully conducted song. Each soldier is a member of the grander symphony and every weapon is an instrument redesigned to have the ability to kill.
I would love to hear what you think about them, and also I could use some help developing them a bit. They seem to have magical attributes--hence the fog and the initial first strike. I would guess that they would be something like elves, but I always feel a little guilty copying Tolkien's elves. I have toyed with the idea of them being slightly more spirit oriented. So they wouldn't be bound to the physical world as much as men and such. Anyway, they need some work, I need some help.

I like it. I like it a lot.
I was drawn to the title of this post because I've had an idea that's quite similar. I invented a world in which the God-figure loves music, and He created the people to play music. The "devil," so to speak, is silence. Once they give in to the temptation to stop playing music, they're more susceptible to be pulled over to the dark side. Music is a weapon against the creatures of the Silence.
Anyway. I like these people; they're really interesting.
Are the weapons actually instruments, or is it magic that allows them to be played as such?

The weapons are actually instruments, but I would think that they could use some magic to help them play even better. I sort of think of the arrows as sort of flute type things that catch the wind in such a way to generate a sound which almost sounds like singing. Different arrows would have different pitches and would be fired in unison to create cords, or slightly separated to create melodies. The swords and spears would be something similar, but they could probably play multiple notes since they remain in the hands of the warriors. The only problem is that it would be a mostly wind filled orchestra. Unless I can think of some more weapons that could be played otherwise. I guess the bows are like harps....

Like those vortex footballs that whistled.

Being magical doesn't mean they have to look like elves though.

I know they don't have to look like elves, but they were the closest thing I could think of. I imagined their music being very elvish.

I'm just trying to think about how these people work. I almost want them to be spiritual beings, but at the same time I want them to be vulnerable to death and decay. Usually I have no problem coming up with some history for a people, but these seem to be shrouded in mist (just like the story).

Maybe I should just continue the story of the Captain and see where it takes me...

The title of this thread made me think of L. E. Modesitt's "Spellsong Cycle," starting with The Soprano Sorceress, which is set in a world in which songs work magic ... after the protagonist (a music teacher and former opera singer from Iowa, who's transported there by magic) has had time to settle down a bit and start to train some musicians properly, she quite literally takes a chamber orchestra with her when she goes to battle, because that makes her songs more magically powerful.

I think that's a really neat idea. So, all the weapons make some sort of sound, so that the battle is a song. That would have a really disconcerting effect on the enemy, but I guess once they started fighting, it would be less like a song, because they wouldn't be in unison anymore.
Would your culture really rely on that mysical quality, with the fog and music, to defeat their enemies? Or are they expert warriors, too?

Ooohhh....that's cool!!! I love it!!

May I have permission to use a version of this idea in my stories? A race that's orientated to music? And they are more susceptable when they are silent?

Permission Granted. I don't know that it is mine to give, but you may have it.