Here's what I think each of the traditional/orchestral instruments symbolize. The image they create can vary on whether they are played in a minor or major key.

- Piano represents light. It pierces through the air and lends gently on your ears..

- Acoustic guitar represents the country. Just listen to country music.

- Electric guitar represent power unrestricted. It's like a juggernaut in a song

- The trumpet represents strength. That's probably why its used for battle charges.

- The flute represents wind and/or air. It can also represent freedom.

- The strings represent darkness. Their sound lingers like an evil in the air.

- The clarinet represents earth. It's used in many songs that sound like the forest.

-bells represent water. Flows very nicely

There are many precussions instruments that I can go into, but I'll only cover some of them.

- Kick/bass drum - represent footsteps.

- Hihat - represents movement

- Snare/clap - I really don't know that they represent, but I usually think of flashes of light when I hear them.

-reverse cymbal - represents breath

SYNTH INSTRUMENTS - they will represent whatever traditional instrument they sound closest to, .except that they will make the image more dreamlike

If you have anything to add to this or I missed something or you just want to comment please comment. :)