what I mean is, when it's it's my desk. My keys player usually does the sound but if it is me, I do go out front and listen, then I monitor thru my IEM. It usually works a treat.
I recently noticed a lack of guitar at a gig (there were 3 of them). Had I not had my IEM I wouldn't have noticed because they all had amps on stage. When he did a solo I couldnt hear him at all. Needed a new mic lead