[ Editor's note:
 [ The article below, originally entitled "The Duo-Art Robot," by
 [ Arthur W.J.G. Ord-Hume, was first published in The Music Box,
 [ Volume 7, Number 2, Summer 1975 (page 75).  Gerald Stonehill
 [ provided a photocopy to MMD from which the text was extracted.
 [ It is reproduced here with the kind permission of Music Box
 [ Society of Great Britain (MGSGB).
 [ -- Robbie

  Mention a cabinet piano-player with a reproducing action and one
  at once thinks of Welte with the Vorsetzer and its wide, red-paper
  music rolls.  But Gerald Stonehill has the world's only Duo-Art
  piano-player.  Featuring an Ampico-built late Duo-Art drawer-type
  action, this cabinet player makes the original Aeolian system look
  somewhat antiquated.  Its owner talked to THE MUSIC BOX about his
  Duo-Art Robot which, from its membrane valves to its vital 36 penny
  pieces, is altogether a rather odd monster.

During the past year British player piano enthusiasts have been
talking excitedly about a brand new machine which has already made
several public performances in recitals of piano music.  If for no
other reason, its name is enough to stir interest in the mechanical
musical instrument buff.  This is the Duo-Art Robot.

Conceived as long ago as 1962, engineered with the close co-operation
of one-time Aeolian Company boffin and now music roll producer Gordon
Iles, and built between 1973 and 1974, Gerald Stonehill's instrument
is designed to play Duo-Art reproducing piano rolls on any piano.
It is a portable concert pianist.

Why did Mr Stonehill spend so much time and effort in making this
machine when he already has a superb Steinway Duo-Art electric grand
and a pedal-electric Weber?

"I was receiving requests to lend my Steinway for Duo-Art concerts and
with my music room on the first floor, each time the piano was moved,
it was slowly being destroyed".  An awkward turn on the stairs was
demonstrably not intended to cope with traffic in 6ft 2in Steinways.

"I wanted to produce something which could be loaned for concert
performances so that I could share my enjoyment with the general
public."

Parts for the Robot began to be gathered 13 years ago, the principal
item and what one might call the central part of the project being the
acquisition of an Ampico-built Duo-Art drawer from the Steinway of an
old lady in Pennsylvania who wasn't crazy on roll-music.  This key
component, a product of the last years of the reproducing piano in
America and built around 1936 when Ampico and Duo-Art had merged, was
collected by a friend and flown to London.  It features the normal
Duo-Art tracker bar with electric roll drive and built into a late
Model B-style drawer.

Improved system

Early on in the project Gerald Stonehill became convinced that this was
the opportunity to improve upon the original Duo-Art system.  Gordon
Iles, Ramsgate-based owner of the Artona Music Roll Company, came into
the picture around this point.  Iles, who was responsible for the later
and final development work at Aeolian's Hayes factory in Middlesex, had
long nurtured ideas as to how such improvements might be brought to
reality.  As an inventor of genius proportions, he soon assumed a major
role in the operation.

A look inside the lower portion of the Robot immediately reveals that
this is no recognisable Duo-Art-type action.  In fact, the expression
system owes more to the Ampico intensity-valve concept.  Gerald
Stonehill explained the thinking and reasoning behind the reappraisal
of Aeolian's original ideas,

"The usual trouble with all Duo-Arts all round the world is that
whereas they might have been efficient when they were new and in
perfect working order, they have since become more and more sluggish.
Now what Gordon Iles and I have done is to make a system which has no
sluggishness at all -- not even the calculated sluggishness.  We have
therefore had to put back into it, with capacity bellows, or, if you
like, an inefficiency reservoir, a controllable sluggishness to get
back to the finest performance which it is thought the Duo-Art was
capable of."

Asked how he had been able to determine this peak of performance and
to be able to design into the Robot an adequate system, he explained:
"Certain functions are called for by a perforation in the roll and
are then abandoned at a certain speed which can be perceived in the
perforations so that they were still in action for a time although they
were switched off -- this is the natural delay in the pneumatic system.
Now if they were switched off by the Robot while they were supposed to
be still in action on the original roll, we knew that the robot was in
fact working too fast."

Having made a capacity bellows (a pneumatic buffer) of the right size
for the theme side -- largely a process of trial and error -- a similar
capacity bellows of the same sluggishness was made for the accompaniment
side in order to copy the observable slowness on the solo side.

The Duo-Art Robot is essentially a one-off experiment and no plans are
in hand for the production of its components.  "Neither Gordon Iles nor
myself would stand in the way of anyone else wanting to copy our designs
and in fact we could probably help them", says Gerald Stonehill.

In construction the Robot is housed in a plain cabinet, access to the
roll being by a full-size hinged lid.  The piano-key fingers are all
individually adjustable and it is here that is demonstrated an ingenious
yet simple solution to a basic problem.  The adjusters on the fingers
are quite small and, even with their felt pads, there was the real
danger that the fingers for the black keys would miss the key during
the operation of the keyboard shift from the soft-pedal.  The difficulty
was overcome by bonding a penny to the end of each black key adjuster
on the Robot.  The penny, with a felt pad beneath, is so placed that
the Robot's finger can always depress the black keys properly.

Like all good robots, the Duo-Art Robot has "feet", only these serve
purely to operate the normal pedals of the piano -- soft and sustaining.

The big spool-box facility of the late-type roll mechanism means that
very large rolls can be played, rather like the half-hour Ampico rolls.
Gordon Iles has accordingly cut some behemoth Duo-Art rolls expressly
for the Robot.

As a utility instrument capable of being carried around to recitals,
the Robot is an obvious success since it will play any piano and, of
course, will play any Duo-Art roll.  In one major respect, aside from
all the foregoing, it differs from the Welte cabinet player: it does
not have an internal pump.  Whilst the Iles/Stonehill Duo-Art system
takes up little space and quite probably the pump could have been placed
inside the cabinet, Gerald Stonehill chose to exclude the potentially
noisy pump and motor.  As a result, the Robot stands connected to its
suction supply by a large-diameter plastic umbilical which stretches
across the music room at Mr Stonehill's home, out through the door,
across the landing, down a flight of steps and into the business end of
a familiar Duo-Art rotary pump.  The result appears to be a measure of
domestic inconvenience, but a commendably quiet power supply to drive
the Robot.

Those who attended the Summer Meeting of the Society heard Mr Stonehill's
talk on his Robot and heard tapes of the instrument in action.  The
Music Box is delighted to advise that Mr Stonehill has promised a series
of technical papers in due course dealing with the design and construction
of various components of this most interesting development.