Pentatonix ( also Acapella band) won a Grammy several years ago for "Sugarplum Fairy". They also did a fantastic "God Rest Ye Merry Gentlemen" in the same style. Voiceplay did a "no words" version of "In the Hall of the Mountain King." It features one of the Voctave sopranos. Very theatrical, great costumes and effects.
That was my only criticism of this--it was too short!! I wanted more. You may want to check out "Where Are You Christmas" (from Voctave--have the tissues close at hand--in a very good way), "O Come All Ye Faithful" (from Voctave--EJ is outstanding), and the Pentatonix version of "Dance of the Sugar Plum Fairies" (from "The Nutcracker"--it's fabulous!).
This is similar to their Great Movie Medley, all but one of the songs is just instrumentals with their voices, it’s insanely cool. I hope you have their versions of O’ Come All Ye Faithful and Mary Did you Know (feat the writer) on your list! ❤
Not sure you picked up the concept of the beginning. It was Voctave simulating the sounds of an orchestra individually tuning and warming up until the conductor stops it and begins the music.