As the laser harp only has 9 beams, you don't get a full octave (with every semi-note), and there are more different/unique notes required for playing RV3 than the laser harp has beams.
So for playing a certain melody, each beam is set up to play a certain note. It seems that he has a pedal on the ...
Blah Blah Cafe, the Jean-Michel Jarre forum
