The performance at the Manchester United Methodist Church is a benefit for the Musicians' Relief Fund.
"I think I get to conduct the orchestra and the audience in 'The Star-Spangled Banner,' which we're going to do in the key of G -- people will find that it's an entirely different experience in a singable key," Keillor said during an interview with the St. Louis Post-Dispatch.
"I'll certainly talk about growing up in Lake Wobegon and my musical background, such as it is -- a checkered background. The audience will get to sing with the orchestra on a few spirituals, and if there are hymnals around, I'm sure we'll find something."
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