Hi All.  Disklaviers have featured fully progressive pedal control for
some years now.  This enables the damper pedal to be set and held at
any of 128 discrete positions.  The exact pedal position data is
recorded and will be accurately reproduced on playback providing the
piano is calibrated.

I suggest you visit the offending instrument and carry out the following
procedure :-

1. Switch it off.  Hold down both the "Fwd" and "Rev" keys while you
switch it on again.  The piano enters Maintenance Mode.

2. Press the "R" button three times to reach the "Loud Pedal"
calibration procedure.

3.  Press "Play"  The pedal will very slowly descend and return.  It
takes about ten seconds to move down and a further ten to move back up.
The instrument is comparing the actual position of the pedal with the
position the controller is telling it to adopt.  It uses this informa-
tion to build a look-up table to which it refers in all subsequent
operations.  Assuming there is no actual fault, the pedalling will now
be perfect.

4. If you want to hear the Disklavier party trick, try running the
"Keyboard Measurement" routine.  This plays all the notes very rapidly,
over and over, starting ppp and getting progressively louder.  As with
the pedals, it compares the data being sent with that coming back from
the sensors and builds a note look-up table.  It does this twice, with
and without damper pedal, to compensate for the weight of the dampers.

You can work through the entire instrument like this.  It will even
provide you with a file of the corrections it has found necessary.
This, in itself, provides a very powerful means of identifying minute
mechanical problems within the action.  In effect, the Disklavier is a
mechanical piano equipped with a permanently available, highly advanced
electronic test rig.

I was a vigorous defamer of solenoid pianos for many years but now
I have to admit that the latest technology goes to remarkable lengths
and really does achieve some impressive results.

Richard Stibbons MIMIT
Cromer, England