My first reaction was "no keyboard" - then I thought of a fine musician who used to turn up at a session I frequented with a Rhodes piano - and I thought "yes keyboard" - then I thought of an accordion player I used to know, and I thought "small" - then I thought accoustic - "trombone", "clarinet", and the dreaded "piffero".

I go with all the comments about "it depends on the musician" - a good player will fit in anywhere. Don, you have my sympathy re. the bongo player. We used to have a guy at our club who would bring a drum or a tin whistle, and was unaware of the danger he placed himself in whenever he played either. Some people should be locked in a room for 24hr with nothing to do but listen to tapes of someone else playing just as badly. If that doesn't cure them, get Leadfingers to hit them with his banjo (the banjo won't mind).

You need someone who plays "th auld black flute" as a yardstick. If you can't hear that flute, the session is too loud, and people should be asked to drop out (in turns) until the balance is restored. This addresses the volume problem.

Another solution is to play tunes that don't usually turn up in sessions - one session I used to frequent started playing tunes from the Shetlands, Faraoes and Norway to "keep out the amateurs". Trouble is, the true "short planks" of this world will try to play anything!