This is generative midi from vcv.. The midi is controlled by two fm modules and then the notes are controlled by a sequencer that is being run at a different time. There is a video version on youtube that is a little longer showing how it is being done and the patch is also available check the youtube links. The music is the effected version so you don't have all the missing stuff to put it back together, but you can probably come up with something interesting if you have vcv rack pro.