Yep, basically. That and the size of the stage. If it's big, you need to be louder. The good old inverse square law rulz. But you're right in that the drummer sets the basic loudness of the group. Which is why I really hate playing with ham fisted bast@rds who've only got two settings on their dynamics control: loud and deafening. I can't be bothered with players like this anymore. Life's too short.