Initially the eye goes to the sax player, then the drummer, and finally that eye contact with the man in the middle distance forms a triangle. (Have you considered cropping at the post on the right, as the the content to the right adds little value to the impact of the image.)
@bob65 I liked your suggestion and just applied it via picmonkey. I wish I'd had more height to work with as it's not a perfect square, but I didn't want to cut off more of the drummer or the sax players' elbow. I think it makes the triangle of the three 'actors' in the scene pop a bit more easily and does get rid of the dead space from the tracks. Thanks!
Great street shot. Actually there are 4 actors in this shot. I think the back to are wondering how the other two got famous enough to get their picture taken.