This folk-music-related post is about participation, not performance. Shapenote singing (aka Sacred Harp) has been part of American life for well over 250 years, and has been sung in Seattle for 30 or 40. A sizeable group of people will gather in Ballard this weekend, at the Pacific Northwest Sacred Harp Convention, to sing it again. When we first attended this event in 2004, we'd never tried singing in this style but, by the......