If you havent attended a Compton Heights Concert Band concert this summer, youre too late their season is over. No wait; checking the schedule, it seems tonight is the actual final performance of the summer. But this is it, the last one. If you flake out on this one, youll just have to wait until next July. The time? 7:30 p.m. The place? Tower Grove Park (4256 Magnolia Avenue; 314-776-2227 or www.chband.org). The special guest? None other than tenor Hugh Smith. The price? Why, free, of course. Maybe you should write this all down, just so there are no horrible scheduling accidents. All right then, run along and have a good time.