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MAY
THE MUSIC TRADE REVIEW
29, 1920
The Design of the Vacuum Systems at Present in General Use in Player-Pianos
Can Be Greatly Improved, and Several Manufacturers Are Already Experi-
menting to Produce a System Which Will Give More Power and Flexibility
It is a curious fact that no pneumatic engi- reed-organ makers were able to perfect an in- the superior tightness. An accurately fitting
neer has been able to design a player action in strument which might be played under any con- piston, freely working, would be better than
which were avoided' the very many inconsist- ditions without laborious effort. At the same bellows, without a doubt, for it would not leak
encies which have hitherto attended it. It is a time they did not allow for any expression as and its efficiency would thus be considerably
matter of general knowledge that the pioneers to dynamic values, save in the one or two cases greater.
in the development of the player were organ in which special arrangements were made to
The same is true of the equalizer, of which
makers. Some of them were pipe-organ men, cut out the equalizers at will by means of an the spring weight could be adjusted very ac-
but most of them took their knowledge and expression stop, so-called. This latter device curately and which likewise would not be leaky
their traditions from the reed-organ. When forms a regular feature of the Mustel har- or slow moving. The size could be much re-
the automatic reed-organ first came into exist- monium, made in France, but is infrequent in duced also for the cylinder and piston would
ence its playing mechanism was drawn from the reed-organ.
work more rapidly and so be more responsive
two sources of design: the paper roll of the
to changes in load. Those who remember the
The Essential Principle
little organette, and the motor pneumatic of
Now it is well known that the essential prin- Gulbransen engine-type motor know that with
the pipe-organ's pneumatic action. The vacuum ciple of the power plant in the player-piano is reasonable care, involving no more than a lit-
power of the instrument was, of course, drawn variability of pressure. That is to say the tle oiling once in a while, the consumption of
from the very same source as the reed-organ pumpers are designed to respond as quickly power was much less and the efficiency much
employed, consisting of a bellows system com- as possible to changes in the speed of the foot- greater than with any bellows motor ever de-
prising two large exhausters and one large work while the equalizers are used only to signed.
equalizer.
steady the flow of power so that the unskilled
These observations are not made for the pur-
The earliest piano-players worked along the performer shall not have too much trouble pose of arguing for changes so much as to point
same lines, of course, for they sprang from with his pedaling. But it is evident that these out that the designs which are in general use
the same sources and were developed by the precautions are of value only in the case of do not necessarily represent the only ways of
same men. In the course of time there have those who will not attempt to learn the art of accomplishing results. When we know that
been many striking improvements, but in one playing the player-piano. It may be thought something we are doing is not giving us the
respect there has been virtually none. We refer that there is no longer any need to talk of this results we might wish for, we ought to be glad
to the design of the power-plant or bellows- art; but the answer is that just so long as the of the opportunity to examine other possible
foot-played player-pianos outnumber all the methods of procedure.
system.
rest there will be every reason to study ways
Fans
The Line of Descent
The cylinder and piston- are not the only
If one examines the power plant of the most and means for rendering the vacuum system as
advanced player action made, one notes that responsive to control as the nature of the case possible alternatives to the wooden bellows.
No one has yet apparently thought of experi-
in essentials it is just the same thing as the allows.
In this case, then, we have a right to ask menting with a rotary fan, driven by power, but
bellows of the original reed-organ or self-play-
's ing organ. The pumpers are smaller indeed why the player-piano designers have not seen regulated by foot. Such a device, equipped
• and the one large equalizer has been replaced fit to think out a new and more suitable system with the proper sort of reducing valve, would
by two of smaller size and of different spring- for their vacuum apparatus. The answer prob- be very responsive and at the same time would
weights; but the principle has not been in any ably is that there has not been enough of a give far greater power than can be had from
demand for improvements. This is rather a any foot-driven device. Of course, neither this
way altered.
Now it must be obvious to any observer that discouraging sort of thing to say, but it ap- nor the other could be compared with the ordi-
nary wooden device on the score of cheapness
the vacuum apparatus of the piano-player is pears to be true nevertheless.
It is plain that the bellows type of exhauster at present prices; but that is not the point. The
not intended to move small quantities rapidly
so as to create relatively high vacuum in a and equalizer has many disadvantages inherent only point worth considering is that there are
small vessel. Rather it is designed to move a in itself. It is leaky, it is hard to move, and directions for research not yet explored which
large quantity slowly so as to obtain a rela- it is incapable of sustaining great pressure. Its will yield rich harvests to any who will have
tively low vacuum in a large vessel. It is there- one and only advantage is that it does not need the patience to follow them through. We have
not reached perfection in any branch of the art
fore plain that the pumping set of the player an elaborately thought out new design.
of pneumatic piano-playing as yet, and there
An Alternative
action follows correctly the reed-organ prin-
ciple up to a certain point; for the aim of the Now it is plain that, for instance, a steel is not much likelihood that we shall for quite a
bellows in the latter instrument is to establish, cylinder fitted with an accurately ground piston while. Certainly we shall not so long as we
and maintain a practically constant low vacuum. would be a much better vacuum device than decline to investigate.
By establishing the principle of low vacuum the the ordinary bellows. Such a piston in such a
The writer is in a position to state that both
cylinder could be moved by the foot quite as of the ideas he has set forth above have been
readily as the bellows, it would not be so leaky experimentally tried out, one in this country
and it could be moved both rapidly and silently. and one in Great Britain. In both cases the
It would also have the very great advantage of results gained have gone far to confirm the
taking up much less space. Moreover, since belief that the ordinary bellows system repre-
the thrust would be vertical and not horizontal, sents a most imperfect development. If they
there would not be the present strain on the were worked out on a commercial basis, the
fastenings, with inevitable loosening sooner or suggested refinements would vastly increase the
9fu? Marter Player Piano
later.
vacuum efficiency of the player mechanism. It
The only trouble would be to provide for may be added that this statement applies as
the lubrication of the piston. Probably this much to the reproducing piano as to the ordi-
Suppose "'APQLI
does cost us bot
could
be arranged by providing that the piston nary foot pumped player. In both, greater
a little
^
power is needed and in both the bellows have
ring should be made of hardened graphite.
The many advantages have been partially reached the limit of their capacity within thej
Tk?APOLLO P U N O C O M P A N Y Ck;«6o-DcO>,IH :
enumerated above. The principle is undoubtedly sizes possible to them.
APOLLO
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STANDARD PLAYER ACTIONS
STANDARD PNEUMATIC ACTFON C O .
538-652 WEST
1?STREET
NEW YORK
CITY