well, it's Taiyo's date because the list came from their web site. They missed out the KN1000 in 1991 by the way.

JVC were pioneers in PCM sampling and recording, I believe some of the first digital master tape recordings released on CD were made on their professional recorders. It's probable the Technics arm of Matsushita bought some of their technology or patents when they stopped making organs, or there was some other link between the companies. Thus Technics would have had a lead in PCM technology while Yamaha had the patents on FM synthesis.