I think you did right John if, as it sounds, you asked him politely even if it was in front of others. He was impolitely trampling on your song and your singing its reasonable to ask him to stop. I've told the story before on Mudcat of the time I lost my temper with a man who continually made noisc during songs. I was upset with him and upset with myself and then discovered that most of the people at song circle were delighted that I had done something even if I did it badly. Ask another singer if the bodhran bothers them. Sometimes we don't share our frustrations with others in a similar situation and yet it can be very helpful to discover you're not weird and suffering alone. If you're not alone then walking away leaves the other singers without your support when a few words quietly delivered might be enough to make the evening more enjoyable for all.

Why bring two bodhrans if you can only play one at a time? Alto and soprano? Regular tuning and DADGAG? Is he trying to start a drum circle?