Originally Posted by: agtierneyok...thanks much.

but can i apply what youve said up there to solos?

Yes it's the same. It's called "transposing". You can take a song in E major and play it in Eb major instead. Many bands do so, especially if the singer has trouble singing in a particular key. But as you try this, I recommend you listen to how the flavor of the song changes if your change the original key. Eb major is a different flavor of sound than E major. The progression of the song is the same but the texture changes. Paying attention to this quality will help you better find the right key for a song you are writting.