I just put together a seller and buyer with one of these beasts.
I ran into it out West in an antique shop.  It was made by Brunswick
and had an early Brunswick Panatrope [fully electric phonograph]
with an amplifier, two loudspeakers and a player piano mechanism.
It was in a private collection and the owner had passed away.
I didn't know these even existed!

Regards,
Donald Cochrane