Tim, I agree with the others on the height, I do a 10k race and a 5k every year , the 10k has a lot more people than the 5k does. I think last year was 1,500 people. What i do on the 10k is this, I have a set of old CGM 15 inch cabinets and a set of pevey pv115 Cabs, I have to have coverage for one whole block , My coverage is about 300' . I place all the speakers about 50' from each other, I am running one side of a Behringer ep4000 and ones side of a Behringer epx2000. Last year the person over the event told me to do it this year just like i did last year. he was well satisfied with every thing. everything was really really loud, but they like it that way so that is what i am running for my 10k gig. the first year I did the gig was a learning experience for me. cause it was my first one ever, I had my speakers setting down low, the people e mailed me and said that i did a great job but they needed it louder, so i started thinking about the height thing and last year I put them above the people's head and that done the trick. it was louder and made the people happy. So get them things up high it will be a great improvement for you. and I would suggest adding a couple more and doing them like i told you earlier. Hope this works for you.