When I came rushing to the defence of Aeolian engineers I was doing
just that, defending them per se and for a job well done for a
particular market.  The discussion now has been broadened to include
other makes of reproducing piano.  Here I must agree with Spencer in
that Welte, and for that matter Ampico, systems are better designed
overall.

I accept that some aspects of the Duo-Art could be better designed but
one fundamental superior aspect is the ability to accent by 'theming'.
The Duo-Art is a theme and accompaniment system whereas the Ampico and
Welte systems are bass and treble systems.  The Duo-Art can get away
with inferior regulator control (by embodiment rather than concept)
as it is able to instantaneously change its suction level from the
accompaniment to the theme, and back again.  The Welte, and Ampico, must
change the regulator level itself to get the same effect, something it
is unable to do as fast.

My conclusion is that the Duo-Art is a better system by concept, but
the other systems are better by implementation.

I also agree with Spencer that if Aeolian had taken greater care in the
embodiment of their ( superior ) design it would have worked well for
longer.  In cold economic terms, however, they didn't do too badly with
what they produced.

I do not understand the comment about modern materials.  These may or
may not last as long as the originals, only time will tell, but I have
no trouble buying materials that do not affect the performance of the
piano once restored.  Materials with a low life expectancy are no
reason to MIDIfy a piano, just restore it more often!

Robbie's comments may refer to the Hupfeld Triphonola which is a theme
and accompaniment system using the familiar snake bite perforations
and two regulators controlled, not by the four-bit digital code of the
Duo-Art, but by floating valves similar to the original Welte.

My upright Roenish Triphonola is so full of well engineered works that
there is no room for the vacuum pump, this going in a separate cabinet
in the cellar (if you could afford a Triphonola you obviously lived in
a house large enough to have a cellar!).

The Triphonola can be considered to be the ultimate reproducing piano.
It can be played electrically with special rolls for full reproducing
quality.  It can be played by pedals with standard or reproducing rolls
or can be played electrically with standard rolls.  It has no background
noise as the pump is elsewhere.  It was Hupfeld's first reproducing
piano to play the 88 note standard format roll, and their last.  It was
preceded by the Phonoliszt and the DEA.  The design and manufacture is
of the highest quality as would be expected from a top of the range
German instrument, and it stands head and shoulders above any American
piano.

Have a nice day.  Nicholas Simons.  England.