The Audience Choir

Jazz musician Jacob Collier always ends his concerts with an audience singalong, but this performance at O2 Academy in Brixton, London, last month is next level. He plays the audience as if it were an instrument itself. How can this crowd possibly sound so good? First off, Collier is known as a musician's musician. His performances draw people who are musicians themselves, or else technically aware of how music works. I wanted to know how he sets this type of thing up. One of the commenters at YouTube explained it.

If you want a more detailed breakdown of the mechanics of the process, he starts off by dividing the audience into 3 sections one at a time just by pointing at them, and giving them a note.  He points up the middle, then to his left, then to his right.  He has perfect pitch, so he can just hear the correct notes in his head.  The starting notes he gives are the root, third and fifth of a major chord, in this case, G major, G B and D.  From there, he then points at a section or sections, and points up or down, and that section goes up or down one step of the major scale from where they were.  Sometimes he controls just a single section, sometimes 2 at once.  Usually both sections go in the same direction, but near the end, one section goes up and the other goes down.  He's literally composing this 3 part harmony in his head as he's waving his hands.  Every show he does this it's similar, but each one is unique.  This one is especially long and complex in comparison to some of the other clips we've seen from his other shows on this tour.  Anyway, hope that helps.

However they did it, it sounds good. (via reddit)