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this auction"Minimoog, Serial # 6581 final assembled (back in the good old days when synths were hand made) on December 21, 1974. Back in the late 80's when I was into at the time revolutionary MIDI possibilities, I decided I wanted a Studio Electronics Midimoog. So I took the cards out and sent them to Studio Electronics to go in the Midimoog I bought from them (I sold the Midimoog several years ago).
A Minimoog with Serial # 6587 recently sold for almost $4000.00. It obviously came with the cards, but if you're willing to wait and find the cards, you'll have a Minimoog that will be guaranteed to go up in value even more as each year passes!" Again, note this one does NOT have the voice board so it obviously does NOT work. Now go look at the price. :) Anyone know what each board was? You can see the slots in this bottom inside shot.