The Villan: if you don't play, you may not realize that forming a circle is for a reason. It takes very little background chatter to make it impossible to hear what other players are doing if they're too far away. The circle puts everybody as close together as possible and makes sure everybody can both see and hear each other - the result is a much tighter sound.

Sessions vary a lot in how far the audience is involved. I'm off to one tonight, at the Tass in Edinburgh, which is at the "performance" end of the spectrum - the drinkers are fairly quiet and they really do listen. They players are mostly not virtuosic (adult learners from the Scots Music Group fiddle classes) but they play their limited repertoire with conviction. In that setting they are putting on something much nearer to a real show than you hear in flashy high-speed obscure-tune sessions led by pros where nobody more than a few feet away from the musicians' table can hear a thing. The result is that the Tass audience regularly drop banknotes on the table in front of me.