The level changes are not extremely big. It might be something like 3dB in either direction. If you are running only a few preset and tweaking them at soundcheck, it would never be a problem. We usually run without soundcheck and without sound guy. I have one preset per song, and the levels are all saved with the preset. So level changes required me to update 60+ presets. I have a system, so it is fairly easy to do but tedious none the less.I have also never had any issues with levels changing, etc. I typically tweak a little at each gig depending on the room so I am used to adjusting gain, master volume and EQ settings using the knobs for certain presets on the fly as needed.