Yes, it's totally her natural voice hitting those high notes! Obviously, her voice is triggering an effects processor to make it sound strange, but it's definitely her. When she sings it live, she uses a different mic for those parts.
If it's worth it to you to download them, I've uploaded a couple more fantastic songs,
here. You have to wait 45 secs for the download and then close the popup (it covers the download link...sorry!). 'Utopia' is from the first album, "Felt Mountain", where you can hear her unaltered high voice in the style of opera! The second song, 'Ride A White Horse' is from the latest album, "Supernature". Here you can tell the difference in music style.
