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THE MUSIC TRADE REVIEW
11
The Fundamentals of Player Design Discussed in a Manner That Is Interest-
ing and Intelligible to the Engineer of Pneumatics as Well as the Layman
—Educational Campaign Inaugurated for Review Readers Worth Attention
In the present and in some succeeding articles,
an attempt will be made to set forth the funda-
mental principles of player design in a manner in-
telligible alike to the engineer of pneumatics and to
the layman. The ideas and arguments set forth
here are based largely upon the ideas and argu-
ments which form the foundation of the instruc-
tion now being given in the Chicago High School
evening classes. So much interest has been roused
In the subject and in the manner of its presenta-
tion that those who are debarred from actual sight
of the work may wish to obtain some notion of
how it is conducted. To an extent, these articles
will fill this desire. But to a still greater extent
they are intended to set forth more clearly, more
in detail and more in permanent form the basic
arguments which must be presented, worked out
and mastered before an intelligent understanding
of the problem of design may be had.
Of course, it is easy to understand that any
mechanic who has worked in a player factory and
is sufficiently skilled with his tools can devise a
player mechanism that will work. But the time of
empirical method, pure and simple, is passing; in
fact has passed. To-day the public demand is sure-
ly shaping itself towards a player mechanism that
shall be in every sense of the term a ''piano play-
er" ; that is to say, something that will play the
piano, and play it rightly. More and more clearly
one decries in the distance thr signs of a new
school of music, of composition and of perform-
ance. One looks ahead a few years to find every
upright piann htted with a player mechanism. One
begins to see dearly the absolute necessity for
clearing the ground beneath our feet in so
thorough a way that the general level of informa-
tion will rise to where it should be, and the way
be made clear for the enunciation of definite rules
of design on which the whole player world can
rest. When'that has been done; when designing
in our industry is like des gning in any branch of
exact applied science, then we shall begin to see
the perfect player. It is for this reason that the
following words are offered to the readers of The
Review in the hope that they will do some good
in the direction of clearing up difficulties and ren-
dering the actual mechanical problems so simple
and clear that they can be understood of all men.
The First Point.
In most of the contemporary discussions which
take place concerning the piano player mechanism,
the opinions of designers, of salesmen, and of lay-
men alike appear to be vitiated by one special
fault. Many of those who "talk player" have a
habit of neglecting the most important point in
the whole argument; nay, the most important point
in any argument that can be made in reference to
any possible form of player mechanism I mean
that they habitually neglect the piano itself.
Xow it should be plain to any obseervant person
that the piano and its action are the most important
things that we can consider, if we are thinking
out player mechanism. We should never under-
take to think out the facts about player mechanism
unless we are ready to begin in the right way. to
begin, in fact, with the piano. Or, to put the nut-
ter in another way, we should not even begin to
think about making a player until we have found
out exactly what that player has to do. And in
the neglect of this point lies most of the difficulty
that has ever been experienced in building really
good players.
Piano Playing.
The mechanical processes that make up the oper-
ative part of piano playing should be the first con-
cern of the olayer designer. All the mass of in-
formation, accurate and inaccurate, which clusters
around the idea of piano touch, as it is called, has
to be sifted down to its smallest particles, if we
would know the facts. They can be known, how-
ever, without much difficulty and without any
mystery.
Piano touch means the action of the human per-
former through his fingers, on the piano hammer,
as transmitted by means of a special mechanism,
called the piano action. The finger depresses a key
which turns on a pivot, communicating its motion
to a series of levers, which, in turn, communicate
a turning motion to the piano hammer. This ham-
mer may be regarded as a point moving in the
circumference of a circle of which the center is
the pivotal point. Thus the work of the finger is
simply to initiate a train of motion through a series
of arcs of circles, culminating in the motion of
the hammer. This latter motion is the goal at
which the finger aims.
Now it should at once be observed that the ob-
ject of the human performer is to produce tones
in such order and of such pitch as he desires for
the interpretation of a piece of music. The piano
is a stringed instrument of music of the percussion
type; that is to say, of a type in which the strings
are struck. The hammers then are the essential
elements in the piano's mechanism, and the per-
former expresses his musical ideas through
manipulation of these hammers. If he could,
therefore, manipulate them with any other part of
himself rather than his lingers, anil do the work
better thereby, then he would do so, no doubt. If,
again, he could manipulate the hammer by direct
pressure of the fingers on them, instead of by a
series of intermediate levers he would do so.
He uses the key, and the piano action simply be-
cause there is no other way so convenient for
the particular kind of organism called the human
hands and fingers.
This is simply another way of saying that the
problem of player design is fundamentally one of
ascertaining, not how the human finger by reason
of its own peculiarities manipulates the hammer,
but how the hammer should be thrown against the
string in order to produce the kind of tone quality
and tone volume from moment to moment re-
quired. To put the matter in other words, the
motion of the hammer is all we need study.
Now this motion is that of a point on the cir-
cumference of a circle. No amount of manipula-
tion of the piano action can do more than vary
the velocity of the travel through this arc. The
piano action is tripped up before the hammer
reaches the piano string; and. consequently, at the
instant of contact with the string, the hammer is
out of the control of the human finger. Hence,
the velocity of the hammer motion is all that can
be controlled. There are other mechanical rea-
sons which may be set forth, but these are essen-
tial. For a more detailed treatment of the prop-
osition the reader is referred to other articles
that have appeared in this section on the mechan-
ical analysis of piano touch.
• •
The Second Point.
The weight of the mechanism which comprises
the piano action, as regards the total load to be
lifted or turned by the player pneumatic, is next
to be considered. Tt is, of course, plain enough
that we control the hammer velocity by con-
trolling the speed of collapse of the pneumatic,
which means again the amount of power made
available for the pneumatic, which corresponds to
the greater or less pressure exerted by the finger
on the piano key. But the pneumatic is the key
of the player mechanism, and the more power that
is placed at the disposal of the pneumatic the
quicker it will collapse (turn through its appointed
path, that is) and thus the more quickly will the
hammer travel to the string. This means a hard-
er blow, as we say.
Weight and velocity are, then, our problems
first and foremost.
Now, since the power which animates the
pneumatic is derived from the pressure of the
atmosphere upon its outer surfaces when the air
inside it has been thinned out by displacement
ot a part of it by means of an air pump (bel-
lows), it follows that the size of the pneumatic,
must be considered with care. For since air
pressure is to be understood as exerted equally
over every square inch of the pneumatic's sur-
face, the more surface there is to (he moving
wall of the pneumatic the more power will be
exerted on the piano action. It then becomes a
matter of remembering that the larger the pneu-
matic the more air there is to be displaced from
it, which means either larger bdlows or quicker
pedaling, or both. Larger bellows mean more
weight to move by the feet anyhow, so that the
compensation of forces remains the same.
Obviously, then, the first thing to understand
is that our player should be so constructed that
the pneumatics may be made as small as prac-
ticable. Small pneumatics mean a small pneu-
matic stack. This, in turn, means less total air
space to be partially exhausted. This, again,
means smaller belluws. This means easier work.
P>ut there are factors U> be considered at the same
time which tend to limit these generalizations.
One of these is the question of what we may
call transmission drop, or loss from leakage.
Another has to do with the relation between the
dimensions of the bellows, the stack and the
pneumatics. All of these must now be consid-
ered. We shall, therefore, devote a later article
to these questions. It may, however, be noted
at this point that no such thing exists as an ab-
solutely leakless player mechanism. Transmission
drop must always b: reckoned with to an extent.
However, it is possible to calculate with reason-
able certainty and accuracy the actual amount of
displacement required to hv performed by a bel-
lows system. To this we shall mxt devote our-
selves.
(To be continued.)
TO IMPROVEJHJARTERS.
The John II. lleaton Piano Co. has just made
contracts for elaborate improvements on the ex-
terior of the company's building at Broadway and
Harmon streets, Camden, N. J.
£
Pass judgment
on them all—
You will then
decide on the
Send for Catalog
Dealers in principal
cities and towns
Emerson Piano Co.
Boston . Mass.