Al Pebworth contributed an image of a 1976 Duo/Art advert,
see http://www.mmdigest.com/Gallery/Pictures/duo=art.html 
At the bottom of the ad is

  Duo/Art - A Division of Aeolian Corporation, Memphis, Tennessee
  the world's largest exclusive manufacturer of pianos

At http://www.mbsi.org/manufacturers.php#A  --

  Aeolian American Corporation. East Rochester, NY. ... ...
  Aeolian-American was acquired in 1959 by Winter & Co., owner of
  many other old piano brand names, which had resumed production
  of spinet player pianos in 1957.  Renamed the Aeolian Corporation,
  and then Aeolian Pianos, Inc. in 1980, it continued to make pianos
  and spinet player pianos under a variety of brand names until its
  bankruptcy in 1985.  The Chickering brand name was then acquired
  by the Wurlitzer Co.

See also http://rocwiki.org/Aeolian-American_Piano_Corporation 
and http://insurancenewsnet.com/article.aspx?id=200134 

Robbie Rhodes, MMD
Etiwanda, Calif.

P.S.: The Hardman "Duo" player piano mechanism is not related to
the "Duo/Art" mechanism found in pianos by Aeolian Corp.