I have a Panasonic cassette/radio boom box from the early eighties. It
has
two thin square metal speaker sheets instead of a cone. The sheets are
mounted on some sort of honeycombed material just a few millimetres
in width that appears to squeeze almost flat from the vibrating sheet.
I still have the unit and think the sound rivals conical speakers. It
is also mesmerizing to watch the honeycomb "pad" squeeze flat and then
outward again.

Anyone else know about this "Honeycomb Speaker System" (as is
actually written right on the square metal sheet) and why it
didn't become more popular and if the properties of the new NXT flat
speakers should be similar?

The model of the unit is RX-C53.

Thanks!