So this happened this past weekend in Atlanta, Georgia, over 600 people attending the inaugural singing convention of the 2025 edition of the Sacred Harp. By my calculations, we could get those kinds of numbers with just 0.0016% of Tokyo. Surely, they're out there if they only knew they needed to do this.
Perhaps we'll have a few less than that this coming Sunday, September 21, 3:30-5:30 pm, St. Alban's Church on the street leading up to Tokyo Tower from Kamiyacho Station. Looking forward to singing with you.