John - many thanks for your valuable advice. I've printed it out and will use it to help me plan the event (and future gigs). I wont treat this as practice though - I practice with headphones on so as not to annoy my wife!

Alain - wish I had all those expansion boards! I'm sure you'll do well with your KN7000. For my situation I'm not planning to use an external amp as this is only for background music. For a previous concert, where I was one of many artists and played only 4 pieces, I plugged into the main sound system which was great.

Regards,
Mike