Okay let's put yourself in the other guys shoes, First off you are a sound guy poof! and as he is one of us a bass player. You get a gig to do sound some guy "Me" is opening his wallet and trusts you know what you are doing. I have promoted the hell of of this show and have tons invested my wallet to you has open to the tune of a few more 0's then you are used to having in your pocket. Every band in the show has a bass player who has a " signature sound" You are a bass player as we have mention and wouldn't want a sound guy to screw up your "signature sound" that's for sure! There are 5 bands I will make it easy on you. You have a colored signal coming from each, one guy thinks he is Billy Sheehan on the edge of feedback, the other guy sound is deep rich bass the next one is Metal with a ton of chorus, the other guy really knows his stuff and is in a Classic rock band who tweaks his amp a little to get the signature sound of every song they are covering last guy is in a punk band. You get behind board and you are ready to kick this show into gear there is a ton of cash going to line your pockets when this thing is over. First band starts and the bass is clacky feedback crazy stuff The crowd is holding their ears! You now are in trouble you need to do something as the $ is slipping through your fingers, because you just shot me a glance and I am looking at you like what the F are you doing! You get through it. 15 minutes later next rig is up booming mud out of control you start backing out everything now to save your a** and it goes on till the show is over! Now that was just your bass mix remember your need to mix the entire band multiple guitarist, different sized drum kits some over hand hitters a keyboard player or two who some of which have busy left hands that has taken bass mixed with the bass guitar through the mains and subs to a whole new level of mud. The chances of you ever working sound for me again are gone! And you can bet your a** after you took it into your own hands to ruin my show after all of my promoting and investment you wont be seeing me open my wallet! See now why Sound men run you direct? The mix no matter who hits the stage is clean fits the band mix and the guy who is paying you is happy to open his wallet for you again next year.