Here's an observation derived from doing a solo act at a lot of different coffee house type venues: On VOLUME; When playing loudly, strumming with abandon and singing full blast, the ambient noise levels of the venue increase. The audience will talk loudly and laugh loudly, and the steamers will run non-stop. Conversely, on DYNAMICS; when finger-picking lightly and crooning airily, noise levels seem to drop dramatically and the staff will wait to fire up the esspresso machine. This was an example of what Brenda emphasized.
Is it me or is there some confusion between 'mixing' and 'mastering'?
I used to belong to a musicians club where anyone could show up and play. The biggest offenders, as far as volume went, were piano players. They would always put their amps on the floor behind them and their VOLUME would blow right past them. What they heard was what reflected off the far wall. The solution was to aim their amp right at their head. This also works for loud guitar players too.

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