I’ve updated the entry to include information about what castrati were- men that kept their child’s voice into adulthood through castration so that they could still sing soprano. And a bit about a famous piece written in the 1600s by a man named Allegri. Both these have cool informational videos. The Sistine Chapel Choir are famous for having employed all castrati for the soprano and alto parts especially during the 17th, 18the and 19th centuries. There are even recordings of them from 1902 and 1904! The choir sang the original fauxbordon with ornaments for over 200 years before a composer named Mendelssohn mistakenly copied down part of the piece in the wrong key! This new version includes a high C for one of the soloists and sounds eerie because it’s in two separate keys.