[ W/R/T Dan Wilson's comments on this topic in digest 961025 ]

Hi MMD-readers,

concerning piano rolls to MIDI coding it must be avoided to mix up two
fully different subjects.

One is the musical information which the rolls contain.

The other is how a reproducing piano is able to convert this
information back to music.

The musical information in the roll was played and then edited by
artists of our century's beginning and is therefore our legacy.  For
this reason we should try to get the original information as true as
possible. Though MIDI has some drawbacks its benefits recommend it for
this purposes.

There are different ways to do so. Some experts derive the data by
computer after scanning a true image of the roll. Others read only the
information given by the punches in the 65 or 98 or 100 rows.  There is
also the possibility to play a roll by a computer driven device leading
its MIDI-output to a digital piano or a DisKlavier for control and save
the MIDI-data with a sequencer program.  The controlling computer
program has to convert the intensity coding just as the reproducing
piano does.  In this case there is no image of the roll but the musical
information, that the reproducing piano feels at its key- and pedal-
pouches reading the roll it is playing, as MIDI-data.

The other subject depends on the instruments quality. But there are
some limitations determined for example by solenoids.  The electric
pulse for low intensities must be not too short as the solenoid needs a
certain time of power to fire its plunger but the time between fast
repetited notes must be long enough to let the hammer (and the plunger)
come to its rest position before the next pulse. (It would be probably
better to controll the power (V/A) instead of the pulse's duration
time).

Working since many years with electronics I admire still the
technicians of that time working with pneumatics and their results, a
playing reproducing piano.

Best regards, Horst Mohr

--
mohr@nemeter.dinoco.DE  H. Mohr Koelnerstr.49 51515 Kuerten 02268/1561