I used to play in a band that did a lot of hotel night clubs (early '80s, remember playing the Sheraton Hotels, etc..? Those were the days, we actually got paid a half decent wage.) Anyways. We would set up and get sound checks usually pretty early in the day.Our first set started around 9:30pm. Since the clubs were usually empty during the day when we set up, then filled up for happy hour and then it rolled over to dinner and then time for us to play. Many, many times the difference in temperature and humidity would change enough between an empty room and a full room that my drums would need some tunning.