In the sacred-harp singing tradition, the phrase “sacred harp” refers to the human voice. Originating more than two centuries ago, the style, also known as shape-note singing, was meant to make singing accessible for folks without training by adding shapes to musical notation. More than 200 attendees are expected to lift their voices in song at Burlington City Hall Auditorium for the 42nd annual New England Sacred Harp Convention. Hosted in the Queen City for the first time in five years, this community singing event kicks off on Friday with a participatory workshop taught by international instructors Buell Cobb and Nathan Rees. Open singing follows on Saturday and Sunday for individuals of all ages and abilities.