Great advice hear ... but all of it, it seems to me says; "learn your sound system and its appilcations"

Fortunato - I am sure that all rooms change acoustically as the crowd grows and shrinks. And I believe it is impossible to run EQ from the stage. You may be able to do OK setting levels, if you have good pre-sets. I believe a band situation normally requires a good sound man. There are always ways to compromise, and do without, but I know as a performer; the last thing I need to be worried about is the sound. I think of a sound man as another member of the band. It's true they can come and go easier then other members, but their professional expertise can make all the difference in your band's success.