IMPROVEMENTS IN STRINGED MUSICAL INSTRUMENTS
Year: 1850

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
CADBY, of Liquorpond Street, in the County of Middlesex, Pianoforte Maker,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain and Ireland,
bearing date at Westminster, the Twelfth day of August, in the fourteenth
year of Her reign, did, for Ierself, Her heirs and successors, give and grant
unto me, the said Charles Cadby, Her especial licence, full power, sole
privilege and authority, that I, the said Charles Cadby, my exors, adñors,
and assigns, and such others as I, the said Charles Cadby, my exors, adiîiors,
or assigns, should at any time agree with, and no others, from time to time
and at all times during the term of years therein mentioned, should and
lawfully might make, use, exercise, and vend, within England, Wales, and
the Town of Berwick-upon-Tweed, my Invention of "IMPROVEMENTS IN
STRINGED MUSICAL INSTRUMENTS;" in which said Letters Patent is contained
a proviso, obliging me, the said Charles Cadby, by an instrument in writing
under my hand and seal, particularly to describe and ascertain the nature of
my said Invention, and in what manner the same is to be performed, and to
cause the same to be enrolled in Her Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said
in part recited Letters Patent, as in and by the same, reference being there-
unto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Charles Cadby, do hereby declare that the nature of my said Invention and
the manner in which the same is to be performed is particularly described and

page_text: ascertained in and by the following description thereof, reference being bad to
the Drawings hereunto annexed and to the letters and figures marked thereon
(that is to say):-
My Invention of improvements in stringed musical instruments relates to
a novel mode of adapting the sounding board to these instruments, and also
to a mode or modes of relieving the sounding board from the downward
pressure of the strings, and is applicable to all the various constructions of
pianofortes as well as to other stringed musical instruments.
The ordinary mode of adapting the sounding board to pianofortes consists in
firmly glueing it to the heavy wooden framing of the instrument in such a
manner that it cannot be removed without being cut away. I have also
sometimes found in instruments of the ordinary construction in which the
sounding board is permanently fixed to the framing that the tone, even of
new instruments, is not bright and brilliant, but on the contrary gives forth a
woodeny tubby sound. This defect I consider arises in a great measure from
the fact that the sounding board is not strained tight, and as no means of
correcting this evil exists in the present construction of pianofortes I have
devised a plan of effecting this object.
My improvements consist, in the first place, in so adapting the sounding
board to the instrument that the former being wholly or partially detached
from permanent connection with the framework and suspended therefrom by
metallic or other attachments may be strained or tightened when desired; and
the parts are so arranged that the sounding board may in some cases be
removed from the instrument should any repairs to it become necessary.
In the best and most improved kind of instruments I prefer that the sounding
board should be entirely free all round and suspended from the framing by
metal clamps furnished with screws, whereby the straining or tightening of
the sounding board may be effected when desired. In the cheaper kind of
instruments where expense is an object, I sometimes ouly partially detach
the sounding board, that is, at one end, or throughout a portion of one end it
is glued as formerly to the wooden framing, but at the sides it is left free, and
at the opposite end it is held by clamps, which being furnished with screws,
admit of its being strained tightly as in the former instance.
In Sheet I. I have shewn back and front views of the internal part of an
upright pianoforte, such as a cabinet or cottage pianoforte. By referring to
Fig. 1 it will be seen that the sounding board A is free all round and is
suspended at both ends by the clamps a, a, a, a; all the clamps at one end of
the board, and some of them at the opposite end, are connected by screws and
screw nuts to metal bars B, B, B, which are bolted to the main framing.

page_text: The remaining portion of the clamps a, a, a, are bolted, screwed, or otherwise
firmly secured to the wooden framing as at C, C, C. It will be seen that the
sounding board is free on all sides, and is not glued at any part to the wooden
framing, but is as it were suspended therefrom by the metallic clamps. By.
this means when the sounding board is strained tight, a greatly increased-
brilliancy of tone is produced. The clamps a, a, are shewn detached, and
upon an enlarged scale in Figs. 3, 4, and 5. Fig. 3 is a plan view; and
Fig. 4 a partial sectional view of one of the clamps used at the lower or bass
part of the sounding board. Fig. 5 is a partial section of another form of
clamp, such as is shewn in Fig. 1 at the upper or treble part of the
instrument; they are precisely similar in principle of construction, although
somewhat different in form. The clamps shewn in Figs. 3 and 4 consist of
two lugs 1, 1, which are connected to one end of a flat bar of steel 2, the
opposite end of which terminates in a round pin 3, which is screwed and
furnished with a nut 4 and washer. The two ends of the sounding board,
whereby it is suspended, are provided both above and below with thin strips of,
wood b, b, b, as strengthening pieces. These pieces are firmly glued to the
sounding board and are embraced by the lugs 1, 1, of the clamps and are
further held by the screw or screws 6, which pass through the strengthening
picces and sounding board. The construction of the clamps shewn in Fig. 5
is so similar in principle to that shewn in Figs. 3 and 4 that it will not be
necessary to enter upon any detailed description of it. Both these clamps being
furnished with screws and nuts admit of a sounding board, suspended thereby,
being strained or tightened to any aniount desired by merely turning the screw
nuts at the ends. The clamps a, a, a, at the part C, C, are not adjusta-
ble, as they merely consist of lugs attached to flat pieces of steel which
are secured to the main wooden framing by screws or otherwise, as shewn
in Fig. 1. These clamps therefore hold the sounding board firmly while
the straining or tightening process is effected by means of the tightening
screws at the opposite side. It will be casily understood that by means
of these tightening screws, an immense strain can be put not only on the
sounding board, but on the framing which has to resist the pressure of the
bars B, B, and as this strain is all on one side of the framing, I have found
(unless some means are taken to prevent it) that the framing will be curved
or drawn in by the strain. I have therefore found it advisable to counteract
the strain of the clamps a, a, a, on one side of the framing, by tie rods
D, D, D, on the opposite side or back, as shewn in Fig. 2. The ends of these
rods are screwed, and furnished with nuts d, and pass through holes made in
the end upright posts of the wooden framing, as seen in Fig. 2, so that by

page_text: screwing up the nuts d, d, a counteracting strain in opposition to that of the
sounding board is put on the framing, which will therefore preserve its original
form. The rods D are also made to rest upon the bridge pieces e, e, e, e,
which keep them back from the wooden framing, and allow the ends of the
rods to have a fair pull in opposition to the strain of the clamps. Vertical
tie rods E, E, are also employed to counteract the tension of the strings, but
this forms no part of my present Invention, it having formed the subject of a
Patent granted to Mr. Hattersley some years since.
At Fig. 6, Sheet II., I have shewn my improved suspension principle
applied to the sounding board of a grand pianoforte. It will be seen, as in
the former instance, that the sounding board is free or open all round, and is
suspended at the two ends by clamps with adjusting screws for straining it
tight when required. The difference between this Figure and those above
described being principally in form, which will be clearly seen and understood
by a simple inspection, it will not be necessary to enter into a detailed
description thereof.
I have already remarked, that in some cases where expense is an object, I
sometimes permanently attach the sounding board .at part of one end to the
wooden framing by means of glue or otherwise; when this is done it is the
curved part marked C, C, C, in Fig. 1, which I permanently attach by glueing
or otherwise to the wooden framing; a beneficial effect is produced, and the
straining or tightening operation may be effected even when the sounding
board is only semi-detached as above explained; but in all superior instru-
ments I prefer to completely detach the sounding board, and merely suspend
it from the framing by metallic attachment.
Fig. 7 represents the suspension principle carried out in a somewhat
different manner, and as it will be less costly I propose employing it for the
cheaper kind of pianofortes where expense is an object. I have also shewn
how the sounding board may be firmly and permanently secured to the
wooden framing throughout a portion thereof, whereby a considerable economy
of construction is effected, and at the same time the sounding board can be
strained tight as in the former instance, thereby greatly increasing the
brilliancy of its tone in comparison with instruments in which the sounding
board is permanently fixed in the usual manner.
Instead of employing clamps with adjustable screws as in the former
instance for suspending the sounding board, I make use of simple lugs to the
hinder part of which small pullies or antifriction wheels 7, 7, are adapted,
as shewn in the detached view of these lugs drawn on an enlarged scale in
Figs. 8 and 9. In place of the adjusting screws and nuts of Figs. 3 and 4,
I

page_text: employ simple straight pins 8, 8, such as are used for holding the strings of
the instrument. These pins are inserted in a wooden bar or beam E, which
forms part of the framing, and a strong wire 9 is secured to these pins, and is
made to pass round the antifriction wheels or pulleys 7, of the lugs, so that
by turning the pins 8, 8, the wire 9 is wound thereon, and by pulling back
the lugs has the effect of tightening or straining the sounding board. It will
be obvious that these pins, wires, and simple lugs may, if required, be always
used in place of the adjustable screw clamps shewn at Figs. 1 and 2, but as
I have already mentioned, I prefer to use the latter in the construction of the
more expensive kinds of pianofortes.
I would also observe, that sometimes I suspend one end of the sounding
board by non-adjustable metallic attachments, such as those shewn at C, C,
in Figs. 1 and 2, or by connecting it to one single bar extending the whole
length of one end of the sounding board, the adjustable clamps being all
placed at the opposite end thereof; or for the sake of economy the clamps
may be made of hard wood instead of metal if preferred. All these various
modifications, and others having the same object in view, (namely), the strain-
ing, tightening, and suspending of the sounding board, it may be found
convenient to adopt occasionally, but under ordinary circumstances I prefer one
or other of the plans shewn in Figs. 1, 6, 7, 8, and 9.
I have found by experience, that although the sounding board when
strained tight is (before the strings or wires are put on) extremely sonorous,
yet when the strings or wires are adapted to the instrument in the ordinary
manner, the sounding board seems to lose a considerable portion of its
sonorousness. This effect is due to the heavy pressure of the strings on the
bridge pieces, which are glued or secured on the upper side of the sounding
board.
The second part of my Invention, therefore, relates to the means whereby
this heavy pressure may be counteracted, or taken off the sounding board, so
as to leave it much freer to vibrate than it otherwise would be. It is well
known that the strings of a pianoforte pass from the pin plate to the bridge
piece on the sounding board, and from thence across the sounding board
to the tuning pins at the opposite side. Now the bridge piece is usually
slightly elevated, so that when the strings pass over it they are bent out
of a straight line, and when the number of the strings is taken into
consideration it will be easily conceived that the amount of downward
pressure on the sounding board is very considerable, and tends very much
to restrict the freedom of its action. This objection I obviate by causing
every alternate string or set of strings to pull the sounding board up-

page_text: wards, instead of allowing all the strings to force or press it downwards.
Various modes of effecting this object may be devised, and I have in Sheet I.
of the accompanying Drawings shewn several methods, but I do not intend
to confine myself exclusively to them.
Fig. 10 represents a section of part of the sounding board of a pianoforte
and some of the other parts adjacent thereto. A is the sounding board;
b, the bridge piece for supporting the strings. This bridge picce is as usual
glued down on the face of the board, but instead of all the strings passing
over the top and pressing it downwards, as is now the case, the bridge is
made a little higher than usual, and the strings are passed through holes
made therein, and from thence to the turning pins at the opposite end. One
end of the strings is secured as usual to pins p, p, in the pin plate E, and
they are passed through holes made in T pieces t, which are screwed into the
plate E; the holes in the T pieces are not on the same level, that is, one is
higher than the other, so that when the strings or wires are passed through
these they reach the bridge at an angle, as shown in the Figure; it will
therefore be seen that the lower wire will press the bridge b downwards while
the upper wire will have a tendency to draw it upwards, and these two
opposing forces being equal, the injurious downward pressure above referred
to will be in a great measure prevented.
Figures 11, 12, and 13 represent sectional, end, and plan views of a modi-
fication of the above for effecting the desired object. In this instance the
strings pass over the top of the bridge, but are held or secured in their proper
places by pins or hooks, whereby the required lift or upward strain may be
obtained.
Fig. 14 is a sectional view of another modification. In this instance the
bridge piece is not glued upon the top side of the sounding board, as is
usually the case, but is fastened on the under side, and the wires or strings
of the instrument are passed through holes in a T piece, which is secured
either by screwing or otherwise on the top side.
Figs. 15 and 16 represent sectional and plan views of a somewhat different
method of carrying out this improvement. Metal T pieces or blocks with
holes made therein are secured to the sounding board above the bridge piece,
and the strings or wires pass direct from the holding pins to the T picces, and
the upward and downward pressure is produced by passing the strings or
wires through holes made at a different level in the blocks on the bridge. I
would here observe, that the above-described improved mode or modes of
relieving the sounding board of pianofortes from the downward pressure of
the strings is equally applicable to instruments of the ordinary construction.

page_text: Having now described my Invention, and the best means with which I an
acquainted for carrying the same into effect, I would observe, in conclusion,
that I do not mean or intend to confine myself rigidly thereto, as other
contrivances or mechanical equivalents may doubtless be employed without
departing from the nature and object of my Invention; but that which I
consider to be new, and therefore wish to claim as the Invention secured to
me under the herein-before in part recited Letters Patent, is,-
First, suspending the sounding board of pianofortes or other stringed
musical instruments by means of adjustable clamps, screws, or other equi-
valent mechanical contrivances, whereby the sounding board may be strained
or tightened when desired, and the brilliancy of the tone thereby increased;
I also claim the use of the rods D, D, for the purpose of counteracting or
resisting the tension of the strained sounding board on the wooden or other
framing of the instrument.
Second, I claim the methods shewn in Figs. 10, 11, 12, 13, 14, 15, and 16,
or any mere modification thercof, for relieving the sounding board of piano-
fortes or other stringed instruments from the downward pressure of the
strings.
In witness whereof, I, the said Charles Cadby, have hereunto set my
hand and seal, this Twelfth day of February, One thousand eight
hundred and fifty-one.
AND BE IT REMEMBERED, that on the Twelfth day of February, in
the year of our Lord 1851, the aforesaid Charles Cadby came before our said
Lady the Queen in Her Chancery, and acknowledged the Specification afore-
said, and all and every thing therein contained and specified, in form above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Enrolled the Twelfth day of February, in the year of our Lord One
thousand eight hundred and fifty-one.