>>>...I would think when you pull the drawbars out, you are taking away from the sound that is "the whole", so would it not be subtractive synthesis?...>>>

I am thinking of a couple of very old organs that I have had the privilege to play. One in particular has no electrical parts. It has knobs called "stops." When I want to add pipes, I pull the knob with the name of the pipe-set that I want toward me. The knob slides toward me 3 or 4 inches. The knob is attached to a wooden dowel that is attached to cables. The cables physically open a set of vales and the valves allow air into the set of pipes I have chosen.


Flatfoot sez: Call me when 'Talent-in-a-Box' is ready to ship! -- [8{>

Got some tunes on You Tube:
http://www.youtube.com/user/flatfoot50
.
My BiaB lesson site:
http://jdwolfe0.wixsite.com/learnbiab