Some years back our choir was singing the "Hallelujah Chorus" along with a musical recording (sans lyric) when the speakers went silent. Fortunately, we had done enough rehearsing to continue a capella without missing a beat. (Maybe a part of a beat.A small church I served as Interim pastor a couple years ago used recorded music, as they had no one to play instruments. One Sunday they had some technical difficulties, so they just sang "a capella." The congregational singing during that time was significantly more robust and enthusiastic!
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