Let's say I teach 7th grade music class... and I want to get a speaker system for our create-a-song project. I want to have a PA that can run vocals, guitar, bass, and a keyboard or two. I could probably get by with 4 channels, but 8 would probably be better. It doesn't have to be too powerful, since we are only in a classroom but it has to be able to blend well with live drums. I don't have too much experience with live sound production so I need some help to know where I should get started. I don't know whether or not to get speakers and cabs for the bass and guitar, or just run everything through a PA. Any help to point me in the right direction would be greatly appreciated. Thank you!