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via
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Pics of the inside below. See
this post for a demo of one.

"This is literally the first sample based synth/keyboard ever made. It paved the way to all of what we have today and was the first of its kind.
I've said it before- I'll say it again- these are rare. Less than 200 of these were ever produced. This is the third to ever hit the market, and the finest and most clean example to ever be offered for sale.

It is in excellent condition and comes with the original manual.
It is Serial #A-201. I am not sure what serial number they started with but I believe it to be very early 1982.
The manual is the second edition printed in 1984 but also states on the title page the manual goes to units Serial Number B-300 and above. So the keyboard is older than the manual. And given if 200 were made, mine is serial 201, and in 1984 they were on B-300. This may be one of the first, if not the earliest unit made.
There is very little known about these units and I did my best to learn and research it.
I do not believe it has preloaded the grand piano sound but has numerous other sounds. There is a photo to see the ROM chips installed with their sounds, and also labels were placed on the buttons for the sound/preset a couple labels are missing. I am not sure if these labels came from the factory or not. And I know that these units varied with what sounds/patches/chips they came with. Some didn't even have all 16 sounds there are buttons for. The unit also does not have MIDI in's or outs labeled "COMPUTER INTERFACE" on the back of the unit - which makes me believe it was early- or they just varied with presets/sounds/features between the units produced. Given the labels are hand written on the chips, and there's no MIDI this could be an early early prototype.
I believe it has 13 sounds installed and has room for 2 more sound chips. Every key and button works fine.
Every feature works just fine... vibrato/pitchbend, all the knobs without issue.
I don't want to call the condition mint- but for its age - it's as clean as it could be. Wood is in absolutely excellent condition, the metal is also, screen printing/labeling/badging all clean. The inside of the keyboard is clean as a whistle- no dust- no dirt. It's the cleanest/finest to ever hit the market. Some light wear on the back, and the back hinge but still - I'd put this 8.5/9 out of 10."