Yes, there is more, but it is hard to figure out what. Maybe they are gluing single notes together. Technical it should be possible. I have a vocal software named Vocaloid. This is a recording of a real artist. You can type in any text you want and the software/singer singes the songs. This is build up by the individual letters. So individual notes for every pitch should be possible too I think. Music libraries are build up like that too.