This isn't the same thing, but there is a "singing" that takes place in a small area outside of Nashville, Tenn called Diana Singing. Thousands upon thousands of people go and take blankets, lawn chairs, whatever, and stay all night and sing together as one voice. It is a once a year thing. I've never been but my parents attended when Daddy was alive, and of course, not ill. They always came back so comforted and happy. Mostly hymns.

JJ