The First Digital Polyphonic Keyboard?

The project by by Michael J. Bauer began in 1972 and was published in 1976.
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"A hybrid polyphonic instrument incorporating the best advantages of both the digital and analog worlds was realised. As far as I know, mine was the first digital polyphonic instrument design ever published (Electronics Australia, April 1976). Unfortunately, the instrument was not destined to be a commercial success. Apart from my lack of entrepreneurial skills, there were other factors leading to its swift obsolescence. The keyboard logic was implemented entirely from small-medium scale TTL devices. It was based on a kind of state-machine architecture. A little invention called the "micro-processor" made my TTL design obsolete. In the same year as my E.A. article was published, Motorola introduced the M6800. I bought a Motorola 6800 'D1' evaluation kit, and so began my career in embedded electronics design."