I have read with interest the recent postings by Craig Brougher and Dan
Wilson concerning the 'Kastonome' accenting system installed by Kastner
in some of their Autopianos.  Some further comments and observations to
throw into the pot:

> I am amazed that the pedals on the piano were apparently ignored
> in deference to note accents, making the roll so laborious to play
> and enjoy.

Is the operation of the sustain pedal really that labourious?  For
maximum musical effect, a pianolist already needs to put expression
into foot pumping, manipulate the hammer rail control buttons and use
the tempo controls.  With a familiar roll, operation of the sustain
pedal lever is not particularly difficult.  However, while I would
never argue against automatic operation being more convenient, does
the average music roll make good use of it?

> ... how was it possible to stack accent holes on top of each other
> in columns and yet get the accent for a specific note on the sheet,
> without also accenting all the other notes in the column, which might
> coincide with some other notes playing...?

I do not have enough knowledge of music to comment on the likelihood
of accent perforations coinciding with unintended playing notes.  One
would assume that the designers concluded that the likelihood of this
is small before embarking on such a project.  As Dan Wilson says,
should such a situation arise the note timing on the roll can be
manipulated to overcome the problem.

Personally, I would have that the chance of unintended accenting is too
small to be of concern but have no way of demonstrating it one way or
the other.  A computer analysis of rolls, not necessarily Kastonome
rolls, could produce some interesting results !

> ... You could forget about tracking a roll on this system...

Automatic tracking, called the "Correctoguide" by Kastner, was
included.  Due to the height (at an inch and a half) and flatness of
these tracker bars, the presence of the suction from the theme holes
could possibly help tracking by holding the edge of roll flat against
the tracker bar.  I have noticed that the edges of rolls, particularly
large old ones, tend not to be held firmly against it.  This causes the
tracking device, which is controlled by the common arrangement of two
pairs of staggered holes, not to operate.

> ... The stack was not ordinary at all ...

Certainly it had to be modified for the inclusion of a Kastonome
mechanism.  However it is possible that a Kastonome stack was an
alteration undertaken on a conventional player action rather than being
a special construction in itself.

Although only 85 playing notes are connected to the tracker bar, the
action stack actually has a full 88-note capability.  All 88 notes are
connected to the back of the spool box.  Plugs were inserted where the
tubing enters the top of the stack to prevent the top three notes from
playing continuously, as a result of not being connected to the tracker
bar.

> ... small delays in theme timing still result in a portion of the
> accent going to unwanted notes ...

Rightly so,  there has to be delay in any system.  I would have thought
though, that those inherent in the Kastonome will be much less than
those in other systems.  The only moving parts are the pouches which
are used to directly switch between suction ports.

Also, since the mechanism works on a per note basis, the quantity of
suction that needs to be altered will be much smaller than for those
that operate on either a whole or half a stack.  The theme perforations
in Kastonome rolls appear not to be offset from the corresponding
playing notes, thus indicating a rapid operation.

> ... The only way I can imagine doing this is by first providing
> a sort of honeycomb isolator wall for each valve in the stack ...

Unfortunately I can not find any diagrams from when I renovated a
Kastner Autopiano fitted with a Kastonome.  The Kastner is a double
valve mechanism, and a disc shaped Kastonome unit is built individually
and separately around each of the secondary valves.  A valve inside
this disc is used to switch the level of suction passing through the
valve -- but don't ask me the details of how this is done.  The valve
shaft passes through the centre of the unit.  Tubes passing through the
main suction chamber connects each of the Kastonome units to the rest
of the theme mechanism.

I can not elaborate on what is inside each Kastonome unit since I could
not find any non destructive way to get them apart.  Admittedly I did
not try very hard as I did not have any Kastonome rolls to play.
However I replaced and repaired what I could and hoped for the best
with the rest.  Experimentation at the time lead me to believe that the
mechanism would work.

>... He never repaired it and when it was sold it went to a restorer
> who simply converted it to a plain player ...

It seems such a shame to remove something just because it is no longer
wanted.  Even if the Kastonome is not working, it could be left in
place with the player piano functioning as an ordinary instrument.
Incidentally, I had been told that my Kastner would never play again.
It did.

Unfortunately, the Kastonome is still disconnected.  This is due to
problems with running the tubing required for the Kastonome from the
back of the spool box to the top of the stack.

The original lead tubes ran from a position located over the hammer
heads to one underneath.  This required them to be shaped around the
back of the hammers.  Due to the advanced state of corrosion they were
replaced by neoprene hose.  Unfortunately, there was a tendency for
the hammers to get caught in it, so producing very uneven playing.
The tubing was removed.  I may put my mind to overcoming this problem.
Any suggestions?

It was the intention, and I hope that I succeeded, to leave the
integrity of the original mechanism intact so that if or when any
Kastonome rolls were obtained it could be brought fully back to life.
This is something that I now intend to do -- I just need the time.

Regards,

Douglas Bush
UK.

 [ A full description of the Kastonome mechanism is given in the book,
 [ 'Pianola', by Arthur W.J.G. Ord-Hume.  A short technical description,
 [ written by Douglas Bush and published in 990920 MMD, is included at
 [ the MMD tech site, http://mmd.foxtail.com/Tech/  -- Robbie