I have been playing out nearly 40 years. I find the best position for the bass amp is directly to the side of the drummer that his high hat and snare are. Reasoning behind this is so you have direct vision to the drummer's positions, his snare, high hat, kick drum and his cymbals. You can then play off or with the drummer and he will hear your bass and play off of you. Remember, you and the drummer are the rhythm section and a team. To be honest I find it throws me off a bit to be positioned any differently. I need to see and feel what the drums are doing. Best of luck on your first show.