There's a joke hidden in this joyful music: Henry Purcell was the composer for Queen Mary and this 1694 composition (Come Ye Sons of Art) was written for her birthday. His court band had two trumpeters, brothers, whose last name was Shore. This section's lyrics read, "Sound the trumpet, 'til around, you make the list'ning shores rebound", But this is the only section of "Come Ye Sons of Art" that has no trumpet part at all, so the Shore brothers had to sit there mute while the rest of the company sang "Sound the Trumpet... listening Shores" dozens of times over.
And yes, those are male countertenors singing. Frankie Valli eat your heart out.