Rule #1: Don't piss off the sound guy!
So for the past couple years I've been attending many concerts and outdoor festivals. All of the mains and subs were different brands and all of the mixes had their own flavor. However....
One of the things that stayed consistent across every single show/festival was the sub EQ. It always seems that around 65hz always has a narrow peak up +12 or even +18db! It packs an awesome punch from the kick and makes a floor tom blur your vision, but whenever bassists play that C on the A string or a keyboardist plays that note it's always skull-splitting. I like to raise 65hz on the kick and floor tom that much but, why do they put that EQ on the subs and not just on the kick and floor tom?