http://www.soundonsound.c...rticles/yamahans10.htm the answer to your question. At the end of this story is this insert-
Goodbye NS10: Yamaha discontinued the NS10 in 2001 on the grounds that they were unable to source the pulp for the bass/mid cone, but I don't buy this. Firstly, they still seem able to manufacture replacement bass/mid drivers, and secondly, it was the cone shape and construction method that were the significant factors, not the specific paper pulp. This however begs the question why
did they discontinue the NS10? I suspect it was a case of ignorance combined with market and margin pressures. Nakamura had moved on to pastures new in the organisation, and those left behind perhaps didn't fully appreciate what was so special about his speaker. It isn't difficult to imagine the sales department reporting back that they needed monitors with more bass, and the engineers responding with reflex loading.