I disagree with the rock addage: If it’s too loud, you’re too old!  Unless you’re KISS, at which point the show isn’t really about musicianship, one of your biggest obstacles is volume.

Playing in a band requires all the musicians to turn their ear towards the live mix.  For some musicians, especially less experienced ones, this is easier said than done.  It can be frustrating for the rest of the band – not to mention the audience (unless you plan on giving out bulk ear plugs)  - when someone’s instruments keeps bumping up in volume.  It can cause some serious band angst when you physically see the offender continually walk over to his amp and crank it up.  I had a band member who was called out on this, so he started adding guitar pedals to his rig that had volume knobs...