As far as I can remember, the Dynavoice was a group invention of
some of the engineers at Daisy Air Rifle Company.

When the ownership and management decided to move their air rifle
manufacturing facilities from here in Michigan to Tennessee (I
believe), some of the engineers didn't want to make the move so they
decided to see if they could come up with something that could use
their field of expertise.  I believe that at least one of them had an
old player piano but couldn't find another one for a friend that wanted
one.  Thus, they came up with the idea to build a unit that could be
used on most 'standard' pianos.

This is the story that I heard when I lived in that area back some
years ago.  Actually, I lived in Willow Run MI at that time, but the
Daisy plant was just over in Plymouth about 18 or so miles away and
I used to talk with another ham operator that worked for Daisy at the
time.

Hal Davis