Just listening to Anny Densmore talk about singing will make you want to burst into song. And as far as she’s concerned, you should start now, even if you’re tone deaf and have no sense of rhythm. But if you’re musically challenged, she has a plan for that. She has a system. It’s called circle singing. Unsurprisingly, it involves circles of humans singing. The number of circles varies, depending on who shows up. “Circle singing is low stakes, big joy,” said Ms. Densmore, a Bolinas composer. “I want people in our community to feel what it’s like to be in the groove—without doing any homework.” A trained facilitator assigns each group parts—simple parts that surge to life on the spur of the moment and that fit together in ways an untrained musician could not have imagined. Experienced musicians like Ms. Densmore make sure the parts fit together in a way that creates some musical magic. One circle might sing counterpoint. A beat boxer might provide percussion. Harmonies emerge. Improvisations erupt. “There are these flavors and textures all going on at once,” Ms. Densmore said. The spontaneous compositions have a way of getting the blood flowing and keeping people in the moment. “We did one at the San Geronimo Valley Community Center and it was packed to the gills,” she said. “Everybody in the room is singing. What’s cool is, you can bring the volume up, and you can bring the volume down. Everybody likes harmony, and everybody likes music that’s in the pocket.” The musical form Ms. Densmore practices began with the king of acapella: Bobby McFerrin, the “Don’t Worry, Be Happy” guy who has nurtured thousands of singers with his rhythmic, call-and-response style. Every Monday in Berkeley, he puts on a show with audience participation at the Freight & Salvage. A regular at the shows is David Worm, who has been singing with Mr. McFerrin for decades. Mr. Worm will facilitate a sing at the Point Reyes Community Presbyterian Church on Saturday, March 30, from 2 to 4 p.m. A donation of $10 to $25 is requested, but no one will be turned away for lack of funds.