(also, sorry for all the previous posts. I hope someone deletes them except one of course. When you press submit post, it just looks like it didn't submit. There's no message or different screen if it submits correctly.)
So I have a Pi and I'm running Samplerbox. One of my midi instruments (not the one I want to user) has a knob that modifies the volume of Samplerbox). My other controllers don't. What pin of my Pi can I connect a potentiometer to to do the same effect (modify volume)?