How interesting to see this instrument restored! And to hear it in action. Steinway's one-and-only Emanuel Moor double-keyboard piano. Several other makers produced one or two of them, and Bosendorfer made several. The history of them is documented in a book by Herbert A. Shead, of which I have a copy (The History Of The Emanuel Moor Double Keyboard Piano. Unwin Brothers Ltd). There is a large fold-out diagram of the action of the Bechstein version, but nothing of that sort on the Steinway. Regards, David.
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