Earliest Known Piece of Polyphonic Music Discovered

A chant dedicated to Boniface, patron Saint of Germany, is believed to date back to the start of the 10th century and is the earliest known practical piece of polyphonic music. Giovanni Varelli, a phD student from St John’s College, was the first to recognize the inkwork as showing two distinct vocal parts, designed to be sung together.
The piece performed below by Quintin Beer and John Clapham - both music undergraduates at St John’s College, Cambridge - gives us an idea of how it might have sounded.

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Thanks Bruce!