Did you know it's possible to sing two musical notes at once?
Me neither.
Singer Anne-Maria Hefele recorded this video to showcase the skill of "overtone singing", and it's amazing to watch.
, where she breaks out the big guns - moving her voice in different directions at the same time.
Anne-Maria is a German singer who specialises in this style of music. Overtone singing is part of many traditional cultures, and is related to throat singing. Check out this archive piece from 1999 when Kongar-ol Ondar,a Tuvan throat singer, appeared on the Late Show with David Letterman.