All of the notions about Duo-Arts being so different is really not
as different as some of the writers believe. First of all, no player
system -- be it Duo-Art, Ampico, Welte, 88-note, PianoDisc,
Pianomation, Concert Master or any other kind -- will play any better
than the piano plays. As a piano technician for many years I very well
know how poor the regulation is on most pianos.
In the last year I have delivered two Steinway XR Duo-Art grands.
Both of these pianos played at extremely soft levels. The regulation
process is exactly the same as any performance piano except at a still
higher level. The longer key is certainly not a problem; a two-to-one
key ratio is still the same regardless of total key length.
What really makes the difference is how even the regulation is from key
to key. We as human players will adapt to slight differences in key
touch or weight and still control our dynamics, while the playing
machines, based on one intensity for the entire stack at any given time,
cannot tell those differences.
No piano makers in the past have ever paid much attention to individual
hammer weights. Touch weight was 'fixed' by placing more lead in the
front of the key to balance the hammer weight. This may give an even
reading for down weight from key to key, but check the up weight and
you will find it all over the place. Balance weight (down weight plus
up weight divided by two) is truly how much weight the player must
move. When I weigh off the hammers from bass to treble in .10 gram
increments, I can even out the balance weights and set very low zero
levels in the Duo-Art.
As anyone who has tried to set levels on the Duo-Art knows, getting all
the notes to play with sustain pedal on and not play with sustain off
is all concept and not reality. We must elevate the low level enough
to play all notes with sustain on even if this lets a few still play
with sustain pedal off. In the action with the touch weight system
installed, I was able to get all notes to play with sustain on and only
four played very softly with sustain pedal off. I have never gotten
this level of accuracy from any other piano without key weighing.
This of course is only one small aspect of piano regulation, but no
less important is the damper regulation in a Duo-Art. Using stronger
springs on dampers does make the setting of the zero level easier as
the spring strength substitutes for evenness in action regulation. The
problem with this remedy is the notes above the dampers. They will
never play very softly with this approach.