US1935215A

US1935215A - Musical instrument

Info

Publication number: US1935215A
Application number: US445655A
Authority: US
Inventors: Victor H Severy
Original assignee: Central Commercial Co
Current assignee: Central Commercial Co
Priority date: 1930-04-19
Filing date: 1930-04-19
Publication date: 1933-11-14
Anticipated expiration: 1950-11-14

Description

Nov. 14, 1933.. v. H. sEvERY 1,935,215

MUS I CAL INSTRUMENT Filed April i9, 195o 5 sheets-sheet 1 *W7* f' 24 i 29 I WA e gmentw Nov. 14, 1933.

V. H SEVERY MUS I CAL INSTRUMENT 5 Sheets-Sheet ATTORNEYS.

Nov. 14, 1933. v, H SEVERY y 1,935,215

MUS ICAL INSTRUMENT A Filed April 19, 1950 5 Sheets-Sheet 5 L/.a/ -2a3 [205 204- l 2/07 as `9.? 2092/0 206' ATTORNEYS.

Nov. 14, 1933. v H. sEvERY MUSICAL INSTRUMENT Filed April 19, 1930 5 Sheets-Sheel'l 4 INVENTOR. 0r 0. eA/ery ATTO EYS,

Nov. 14, 1933. v. H, sEvERY 1,935,215

MUS ICAL INSTRUMENT Filed April 19, 1930 5 Sheets-Sheet 5 A TT EYS.

lllllk- 35 musical instrument.

Paie-med Nv.iui4, i933 i 1,935,215

UNITED STATES PATENTv OFFICE MUSICAL INSTRUMENT Victor H. Severy, Los Angeles, Calif., assignor to Central Commercial Company, Chicago, lll., a corporation of Illinois Application April 19, 1930. Serial No. 445,655

3 Claims. (Cl. SKL-409) This invention relates to a musical instru- Figure 4 is a perspective broken away and ment and the general object of the invention is showing two vibrators of the tuning fork type to provide a simple construction for a musical mounted in amusical instrument and illustrating instrument which will be capable of producing how my apparatus is adapted for use with ham- 5 music in pure tones and capable of being conmers such as employed in an ordinary piano 60 irOlled by Simple mean-S Such aS er1 Ordinary action for actuating the vibrators to produce the piano keyboard or through the agency of automusic, f matic Controlling means of any type, for exam- Figure 5 is a diagrammatic view illustrating D1e,Sl1Ch aS employed irl eutOmatiC pieno Playersdetails of an adaptation of the apparatus 'en- Olie Object 0f the preerli? 'invention iS te abling the vibrators to be actuated and con- 65 Provide means for producing, the tones eone" trolled by an electric circuit and in which the Spending to'notes 0f en y desired musical Seele action of the vibrator is automatically dampened. and t0 Provide cooperating means for enabling Figure 6 isavertical'section taken about on the the tone producing vibrations to be amplied and line 6 6 of Figure 5 and further illustrating de-' l5 translated through the agency of an electric curtails of the Strikerhead which may be employed 70 rent to produce the musical sounds so that they to start the Vibration of the Vibrator will be readily audible. s Fi .i sure 'l is a diagrammatic illustration of the A further obJect of the invention is to provide general Character shown in Figure 2 but mus a musical instrument in which a series of vitratin a aratus of the t e shown in F1 ure 5 bators may Pe emp10yed-capab1e of Vlbraimg ai togethger liiiriith an automatiii controlling ievice 75 different penods respectively* Correspondmg to such as a music roll or perforated web and illusdifferent notes, and to provide simple meansfor' Hating also how the same apparatus can beutilizing the said vibrations to develop impulses, and to amplify the same, the general purpose be controlled when desired through the agency of keys on an automatic piano keyboard. ing-to insure urit of tone in the music reduced. A further iajecty of the invention is tg produce Flgure 8 1s a 51de eleva'tlon. and partial Seamen au instrument of this type iu which inequality, through. an eiecir'mePhamcai. damper device that` is, the timbre, or color of the musical notes suol? as musirated.m Flgure 7 may be varied at will' Figure 9 is a diagrammatic vievv illustrating Further objects of the invention Will appear an apphca'tion of the Invention m which the 85 hereinafter. l quality of notes produced may be controlled at The invention consists of novel parts and com- Wm and. illustrating a' connectlon for enabling binations of parts to be described hereinafter, the.mus1c tope brqadcast all of which contribute to produce an efficient Figure. 10 1S a diagrammatic View illustrating o the application of the invention to a reed type 90 A preferred embodiment of the invention is of Vibrator inwhich the vibrator iscaused to described in the fouowing specification, while the vibrate Without percussion broad scope of the invention is pointed out in the Figure 11 is ,a diagrjammitic View Similar to appended clalms Figure 10, but illustrating diagrammatically the l0 ln the drawings; application of the invention to the reed type of Figure l is a diagram illustrating a Simple vibrator actuated by percussion and in which params which may be employed fdr practicing the regenerating circuit illustrated in Figure 10 is my invention. This figure may be considered as aise empioyed- D illustrating the elemental unit from which a Before Preeeediiig t0 a detailed description Of musical instrument to produce any number of the invention it Sheuld be Stated that the appa" 100 different tones may be Constructed ratus includes a plurality or vibrators construct- Figure 2 is also a diagram illustrating a pluraled JC0 Vibrefe al? different definite PeIOdS I'eSDeC- ity of vibrators combined with my apparatus and tively Corresponding t0 the different notes Of a including electrical circuits enabling the appagiven Seele- Any JyIle 0f VibratOr may be emratus to be completely controlled by means DlOyed Or this DUIIJOSe, butinthe Present Spei- 105 such as a keyboard. cation I have illustrated tuning forks used for Figure 3 is a detail fragmentary view particuthis purpose. Such fOrkS may be readily prolarly illustrating the means for mounting the cured and are very dependable t0 vibrate at the vibrator when the same is of the tuning fork denite period of the fork. Furthermore, they type. will maintain this property for long periods of 110 time. Such forks are now largely used for tuning musical' instruments of different kinds.

My apparatus also includes means for developing electric impulses in an electric circuit to correspond with the vibrations of the vibrator, and these impulses may be employed directly in sound translating devices to produce the tone corresponding to the different vibrators.

I prefer, however, to employ amplifying means in connection with the circuit for amplifying the impulses, thereby enabling the pure tone of the vibrator to be reproduced in a readily audible tone.

Referring more particularly to the parts and particularly to Figure 1, 1 represents a tuning4 fork, the handle of which is tightly supported in a bracket 2, being embedded in a packing 3 adapted to absorb vibrations. Adjacent the tines 4 of this fork I mount' electrical means which will be affected by the vibration of the tines. This means includes an electric coil 5 held xed adjacent the tines and provided with an armature, the poles of which lie adjacent to the faces of the tines so that when the tines vibrate they will approach and recede from thel poles of the armature. I prefer to provide an armature 6 in the coil located between the tines and with its end faces or poles quite close to the face of the tines but not so near as to be touched by the tines when their Vibrationslhave the greatest ampliy tude.

The coil 5 is connected up with an electric circuit 7 including a battery 7a which is connected up with a sound translating device 8 such as a loud speaker. The circuit also includes the controller means capable of controlling the closing of the circuit so as to produce the tone of the Vibrator in the loud speaker. The apparatus may include regenerating means, the operation of which is to employ the vibration of the fork to affect the electrical apparatus so as to build up the amplitude of the vibrations. In order to accomplish this I prefer to employ an electric device 9 having the essential characteristics of a device commonly called a pick-up. This device includes a small armature 10 in the form of a bar mounted to rock on a pivot 11 near its middle point, being held in position between pole pieces l2 and 13 carrying coils 14 which are connected into an electric circuit 15 excited by any suitable electric means, such as a battery 16. The bar 10 carries a coil 17 which is connected into a circuit 18 having a conductor 19 and a conductor 2O leading to the input side of an amplier 21. Connected into the conductor 19 I provide a rheostat 22. The output side of the transformer is connected through

conductors

23 and 24 to two series primary coils 25 and 26 of the transformer 27.

This transformer includes secondary coils 28 and 29 in the form of rheostats connected into the

conductors

30 and 31 that form thesides of the circuit '7. The circuit 7 may be closed at will by any suitable controlling means, for example, a key 33 carrying an insulated contact that is connected to a conductor 34 leading to the loud speaker 8 and a fixed contact 35 that cooperates with the movable contact to close the circuit when the key is depressed.

In the operation of this apparatus, when the key is depressed the closing of the circuit through the transformer results in the development of current in the coil 5, thereby energizing the core 6 of the coil. The core therefore attracts the tines 4 of the fork. Due to the resiliency of the fork, the tines will recede from the core 6. The movements of the tines, through a connection 36 from one of the tines to the bar 10, will cause a rocking of the bar 10 and coil 17 on the pivot l1. This rocking of the coil will generate impulses in the coils l4 which will be felt at the amplifier 21 which will cause impulses in the coils 25 and 26. These impulses, through the coils 28 and 29 will affect and amplify the impulses in the circuit 7 and in the coil 5. In this way, after the fork is started to vibrate, it will maintain itself in vibration and produce a continuous tone corresponding to its rate of vibration as long as thc circuit remains closed at the contact 35.

The connection 36 is preferably of a slightly flexible or resilient character. Otherwise, it preferably includes one or more joints. The point at which the connection 36 touches or connects to the tine of the fork is preferably at a point on the tine that will vibrate. In other words, this connection should not be located at a node.

Apparatus of the character illustrated in Figure 1 can be readily utilized to construct thc musical instrument as illustrated in Figure 2 in which I illustrate an instrument of this character having seven vibrators. In this view I illustrate two banks 37 and 38 of vibrators in the form of tuning forks 39. Corresponding to each fork I provide an electric coil 40 with an armature located between the tines of the fork connected by a circuit through wires 41 and 42 with a corresponding transformer 43. This is a balanced transformer of the type illustrated in Figure 1 comprising two pairs of oppositely disposed coils arranged as illustrated in Figure l. Each transformer 43 is connected on the output side to two wires 44 and 45, the former of which runs to a corresponding key 46 of a keyboard 47 and connects to a switch operated by the key, as illustrated in the key 33 in Figure 1.

From the key a return wire 48 connects to a trunk wir 49 thatleads to a sound translating device suc as a loud speaker 50. The other side of the loud speaker is connected to a trunk wire 5l to which the wire 45 is attached. In addition to this, each fork 39 may be provided with a regenerating circuit, such as illustrated in Figure 1, including a pickup device 52 corresponding to each fork and having an oscillating coil such as the coil 17 (see Figure l), the ends of which are connected to wires 53 and 54 that lead into a corresponding amplier 55. This amplier is connected by wires 56 and 57 with the input side of the transformer 43.

It will be seen that the arrangement of wiring in Figure 2 contains the elements of the wiring shown in Figure l1 but represents the different keys connected up to trunk wires 49 and 5l that lead to a common sound translating device or loud speaker. If desired, a plurality of loud speakers can be employed connected either in series or parallel between the two trunk wires 49 and 51, said speakers being adapted for faithful reproduction of sounds at different points on the musical scale employed.

The exciting coils of the pickup device 52 can all be connected in parallel between

trunk wires

58 and 59 connected to opposite sides of a battery 60.

Instead of constructing the device so that the mere closing of a circuit by a key will produce a desired note, I may mount the forks in a frame capable of being actuated by hammers such as employed in a piano action for striking a piano lll() string. This is illustrated in Figure 4 in which 150 the coil spring 87, already referred to.

61 and 62 represent two forks located adjacent to each other and mounted in a frame 63 and in a position to be struck by piano hammers 64 carried on levers 65 such as usually employed in a piano action. These hammers 65 afford means for starting the vibration of the corresponding forks when given keys of the keyboard are struck. The vibration of the tines of the forks develop impulses in coilsy 66 set between the tines of the forks as illustrated and thereby develop impulses in the

circuit wires

67 and 68 that connect the ends of the coils with

trunk wires

69 and 70 that lead over to amplifier 71 that is connected on its output side with a sound translating device, such as the loud speaker 72.

Above the forks a damper rail 73 may be provided supported on operating levers 74 which normally hold the damper out of contact with the forks but which can be operated when desired by any suitable means such as used in a piano, to depress the damper onto the forks and stop their operation.

If desired, this construction may include a switch 75 which closes the circuit through the

wires

69 and 70 and through the amplifier 71.

If desired, the vibration of the forks can be produced through the medium of a blow struck by an electrically operated hammer. This arrangement is illustrated in Figure 5 in which 76 represents one of the tuning forks located directly vover a corresponding electric hammer 77, said hammer including a solenoid coil 7-8 having a soft iron core 79 or its equivalent projecting from its low end and carrying a stem 80 of non-magnetizable metal at its upper end so that when current ows through the coil 78, the core 79 will be pulled up and cause a head 81 carried at the upper end of the stem 80, to strike the lower tine of the fork 76. The head 81 may carry a cushion tip 82.

I prefer to provide means for automatically damping the vibration of each fork shortly after the hammer 77 has struck its blow. For this purpose, below the fork I provide an electrically operated damper 83 comprising a pair of solenoid coils 84 that operate, when the current flows through them, to draw down an armature 85 and withdraw the damper head 86 from its normal contact with the tine.

The coils 84 are actuated at the same instant that the electric hammer 77 is actuated, so that at'the instant that the blowl is struck by the hammer the damper head 86 .will be out of contact with the fork. However, the damper head is immediately returned by a spring 87 to its normal raised position. The details of this electric damper are illustrated more fully in Figure 8. Each coil 84 is provided with a fixed tubular pole piece 88 which operates as a guide for one of the stems 89 of the armature 85. The lower ends of the pole pieces 88 rest at their lower ends on a bar 90 through which the stem 91 is guided. This stem extends down from the lower side of the armature 85 at its middle point and carries in Figure 8 are' shown in active operation with the head 86 slightly withdrawn from the underface 92 of the fork. As soon as the energizing current flowing through the coils 84 ceases, 'the spring 87 immediately returns the head 86 unto contact with the fork. The coils 78 and the two coils 84 of the electric damper may be connected up in parallel in an electric circuit 93, including a battery 94 and a pair of normally open contacts `95 closed by the depression of a keyj 96 The parts' pivotally mounted at 97, and carrying. an insulating bridging contact 98 on its underside. This key is normally held raised by any suitable means, such as a spring 99.

Between the tines of the fork '76 a coil 100 is provided to perform the'same function as the coils 66 and the coils 5, already described.

If it is desired to have the electric hammer strike a quick blow and withdraw immediately from the fork, I may construct the head 81 as illustrated in Figure 6. This view represents the head in the act vof striking the fork. The head 81 is mounted with a lost motion connection on the upper end of the stem 80, said stem having an enlarged collar 101 on its upper end, and that moves between the

faces

102 and 103 on the head 8l. With this, construction of head it will be evident that when the stem 8O is actuated by the electric coil '78, the head 81 supported on the upper side of the collar 101 will be driven up against the face 92 of the fork. The lost motion connection between the stem and the head enables the stem 80fto be stopped short of the position in which the collar 101 would force the head 81 against the face 92. In other words, the

blow can be struck by the head 81 -advancing by reason of its own momentum. In order to enable the stem 80 to be stopped adjustably at any point desired, the lower end of the core 79, is threaded to receive an adjustable nut 104 and a check nut 105.

.If desired, the invention may be adapted for operating the vibrators through the medium of a control device of an automatic nature, such as the music rolls (perforated webs) of player pianos. This is illustrated in Figure 7 in which 106 indicates such a perforated web running between two spools 107 across a tracker board 108. The tracker board has a perforation 109 corresponding to each fork or vibrator and each perl foration is connected up by a tube 110 to a corresponding bellows 111, said bellows is normally maintained in collapsed state through the agency of a vacuum chamber or air pump connected up lto a vacuum tube 112 that connects with the bellows. When the perforation 113 in the web registers with its corresponding perforation 109 in the tracker board, the Vacuum is broken and the air pressure admitted to the bellows causes the movable side 114 of the bellows to move out and close a circuit 115 through the agency of a movable contactA 116 on the bellows that comes against a relatively fixed contact 117 connected with the circuit 115. The circuit 115 includes two conductors-118 and 119 which lead over and connect up to an electric hammer 120 and' an electrical control damper 121 constructed and wired as illustrated in Figure 5.

The circuit 115 may include a battery 122. The i instrument includes a plurality of forks 123 each of which has a corresponding coil 124 located between its tines and connected up by

wires

125 and 126 that connect to trunk wires 127 and 128. The ramplifier 129 is provided connected to these trunk wires by wires 130 and 131 and theoutput side of the amplifier is connected up to a sound translating device or loud speaker 132. y

If desired, this instrument can be operated at will through the agency of a keyboard such as a piano keyboard, the keys 133 of which are illustrated diagrammatically in Figure 7.v These keys are constructed as illustrated in Figure 5 and when any key is depressed an insulated contact 134 carried by the key bridges two contacts on 1w the ends of

wires

135 and 136 that connect respectively, to the

wires

118 and 119.

I shall now describe briefly the general mode of operation of the apparatus. In the apparatus I illustrate in Figure 7 the forks 123 which may be v ibrated either by the keys 133 of a keyboard or by an automatic control device, such as a perforated web 106. When operated by the web 106, when a perforation 113 in the web comes opposite a corresponding perforation in the tracker bar 109, the partial vacuum normally existing in the corresponding bellows 111 is broken, whereupon the moving side 111 of the bellows moves outwardly and brings

contacts

116 and 117 into engagement, thereby closing circuit 115 which cnergizes the

coils

120 and 121.

This causes the electrical hammer (see Figure to drive its head 81 against the underside of the fork, thereby delivering a blow which starts the fork vibrating. At the moment that this occurs the coils 121 will have withdrawn the damper head 86 from contact with the lower tine of the fork. 1f the hammer head 8l is constructed as illustrated in Figure 6, the blow on the fork will be struck through the momentum of the head, which carries the head on after the stem 80 has been stopped through the operation of' the adjustable stop nut 104 when the same strikes the lower head of the coil 78.

The vibration of thetines of the fork 123 causes impulses in the coil 124 corresponding to the active fork and these impulses, of course, will correspond in rate to the rate of vibration of the fork. In this Way, impulses in the coil 124 are imparted to the

trunk lines

127 and 123 that connect by wires 130 and 131 to the amplier 129 which operates to impart amplified impulses at the same rate to the loud speaker 132.

`. Instead of employing the electrical hammers 77 constructed as illustrated in Figure 5, the apparatus illustrated in Figure 4 may be employed in which the forks are caused to vibrate by-being struck with hammers 64 such` as employed in an ordinary piano action'.

Associated with the forks a damper 73 is provided for damping the action of the forks after they have been struck. The action ofthe forks 62 on their coils 66 in the apparatus shown in Figure 4 is the same as that described in connection with the operation of the apparatus illustrated in Figure 7.

The apparatus illustrated in Figures 4 and 7 is particularly adapted for producing music quite similar to that produced on an ordinary piano, that is to say, music in which the'notes are not long sustained. The apparatus illustrated in Figures 1 and 2 is particularly adapted for producing continuous sustained notes of uniform loudness, that is to s'ay, any note when sounded will continue to sound with a pure tone ata uniform loudness.

In the elemental apparatus illustrated in FigureA 1 which shows the circuits corresponding to a single key of a keyboard, a regenerating effect is attained whereby the vibrations of the tines of the fork cooperate to increase the intensity of the impulses which started their vibration. In this construction, when the key 33 is depressed, a circuit is closed through the

wires

31 and 34 and through the sound translating device 8, and this circuit also includes portions of the balancing coils 27 and 28 which are hand controlled rheostats, used to balance the impedance of the circuits of loud speakers with the pickup circuits.

The disturbance in the coils and 26 is divided equally as to periodicity but not as to resistance balance as the coil 5 which serves to keep the fork vibrating has not the same impedance in its circuit as the loud speaker 8.

The vibration of the fork is sustained by the little electric pickup feeding its small current pulsations from its coil 17 over the wires 19 and 20 into the input side of the amplifying device andy out by wires connected from the output side of the transformer, to the conditioning or impedance balancing transformer to the loud speaker over the wires and 34 through switch 33, and

contacts

32 and 35. When this switch is closed the audible side of the circuit is connected and a continuous tone is heard. The primary or generating circuit is always generating timed electric impulses when the oscillator is started, but only is allowed expression into sound waves, through the loud speaker, when the audible circuit is closed by the keys, operable by the organ player.

-In Figure 9 I illustrate an adaptation of the invention to the production of notes of different color, qual-ity or timbre. In order to accomplish this I provide a plurality of vibrators, for example, tuning forks capable respectively of producing the fundamental and other partials of the different notes. The vibrators for each note are caused to operate in unison by the same means, for example, a single key. By any suitable means, fork example, a switch, I determine which partials of the note will be produced. As illustrated in Figure 9, 133, 134 and 135 illustrate any three keys of a keyboard. Corresponding to the key 133 I provide a plurality of vibrators, in the present instance, tuning forks 133a, 133D, 1330 and 133d. The vibrator or fork l33a is capable when vibrating of producing the fundamental of the note corresponding to the key 133; the vibrators 133D, 133e and 133d will produce the second, third and fourth partials of this note. These vibrators may be caused to vibrate by means such as illustrated in Figure 1, but in the present instance I have illustrated them as being vibrated by a percussion device or hammers 136 corresponding to each vibrator.

Corresponding to the key 134 I provide similar vibrators indicated generically by the numeral 137 which are all connected up and arranged in the same way as the vibrators corresponding to the key 133. If desired, the vibrators may have regenerating means forgiving increased volume .to the note produced, including coils 138. Similar coils 139 are provided to correspond with the key 134 and likewise, as to the vibrators 140, that correspond to the key 135.

The corresponding partials are all connected together on branch circuits so that all the keys of the manual will combine the same partials, and switch means is employed so as to enable any number of the partials to be employed. For example, all of the second partials only may be sounded, or the second and third partials, omitting the fourth partials, etc. and any partial may be made to predominate i'n the note produced. In order to accomplish this I provide a switch 141 corresponding to the second partials and controlling movable contacts 142 which whenv closed, close a circuit from the ground through conductor 143 which connects with a main conductor 144 with branches 145 correspending to electrically operated switches 146. Each switch 146, when energized, brings mov- .able contact 147 together so as to close the branch circuit through a corresponding wire 148 that is capable of energizing the electric hammers 136.

Corresponding to the second partials I provide a switch 149 that operates similarly to the switch 141 and when closed, closes all the electro-mechanical switches 150 that correspond to the second partials.

Similar switches 151 and 152 correspond to the third and fourth partials and 'close corresponding switches 153 and 154. When all of the partial switches are closed an'y of the

keys

133, 134, 135 and any other key of the manual will produce av tone including the fundamental and the second, third and fourth partials.

If desired, manually operated switches 155 may be provided corresponding toall of the electric switches 146 and

similar switches

156 and 157 may be provided in connection with the .wiring connected withl the

keys

134 and 135. For the purpose of illustration these switches are illustrated 4in Figure 9 as being controlled by three separate shafts, but in practice they can all be in line with each other and operated by a single shaft.' Such ashaft should be provided with cams or tappets 158 that bring the contact members of the switches together to.closethe circuit.

It should be understood that the apparatus and wiring for the two keys 134 and the other keys

l trunk wires

168 and 169, the

on the manual will be' substantially the same as the wiring and apparatus illustrated in connection with the key 133. If desired, each vibrator can be provided with a damper 158 similar to the dampers already described. When any key, for

example' the key 133, is depressed, current flows from the ground at 159 through a switch 160 that becomes closed by the depression of the key and from this switch the current Iflows over a wire 161 and through the battery. 162, and thence -through a trunk wire 163 having branches 164 corresponding to the diierent switches 147, 150, 153 and 154. If all of these switches are closed, all of the electric strikers 136 will be actuated to strike their corresponding vibrators or tuning forks, the current flowing fromthe coils of the hammers to the ground at 165. If dampers 158 are employed the coils of these dampers are connected in parallel by wires 166', which are also grounded at 165. l

The regenerating circuits forthe different regenerating coils 138 are formed by means of

wires

166 and 167 that connect respectively with two ends of which connect up to an amplifier 170, the output side of which connects 'to a sound translating device such as a loud speaker171. If desired, one of these conductors, for example 168, may be provided with a hand controlled switch 172.

1f desired, the apparatus may be employed for broadcasting. This may be accomplished in a simple manner by connecting the

wires

168 and 169 to a doublev knife switch 173 connected to an amplifier 174, the output side of said. amplifier having a sending circuit grounded at 175 and connected through a rheostat 176 with a suitable a wire 187 connected with the other end of the coil, through the input side of an amplifier 188; the output side of this amplifier is connected by wires 189 to a conditioning transformer 190, the output side of which ,is connected by wires 191 to a sound translating device or loud speaker 192. A regenerating coil 193 is connected by wires 194 to the conditioning transformer. The wiring of the conditioning transformer is substantially the same. as that illustrated in connection with Figure 1.

The reed 178 may be provided with an adjustable weight 195 mounted on an adjusting screw. By changing the position of this weight the vibrating time of the reed can be very accurately tuned to produce its note accurately.

The core 180 moves between two exciting coils 196 energized by any suitable source of electricity such as a battery 197.

The wiring arrangement in Figure 11 is substantially the same as4 that described in connection with Figure 10 except that in this apparatus thereed 198 is operated by the percussion of a hammer head 199 Which may be in the form of an electric hammer, the coil 200 of which is energized 100 Vby closing switch 201 through the agency of a key In the operation of the apparatus illustrated in Figures 10 and 11 the upward land downward motion of the core 180 of the pickup produces 105 variations in the current passing in the input side of the amplifier, thereby producing corresponding variations or impulses in the regenerator coils 193, thereby maintaining the reed in vibration. This apparatus will give a sustained note like that produced by an organ.

The color and tonal gradations of the partials as produced in the apparatus illustrated in Figure 9 can be determined by two factors, namely, the size of the tuning fork and its pitch, or by the resistance placed in the electric circuit wire passing-through the coil of the electric hammer. In other words, the resistance in the hammerfcircuits can be regulated to determine whether the -partial is weak or strong. In this way the color ments characterized by the predominance of certain partials.

InFigure 1 I illustrate

wires

203 and 204 corresponding to the wires illustrated in Figure l9. These

wires

203 and 204 are trunk wires connected respectively to the diiferent vibrator circuits. Between these

wires

203 and 204 vibrators, such as

tuning forks

205, 206 and 207, for the different partials of the corresponding main tuning fork are provided, said `partial tuning forks being sounded through the medium of coils 208, respectively. These coils 208 are connected into branch wires 209, each having its own switch 210, and these branch wires 209, beyondthe coils, connect up to a trunk return wire 211, one end of which is connected to the vtrunk 204.

Associated with each of the

switches

141, 149, 151, and 152, I provide a battery 143a (see Figure 9) which is in the circuit closed by each switch.

The circuit wire 186 connects with the battery 186e (see Figure 10).

The circuit closed by the switch 201 that passes in the note and to their relative intensity. According to my invention I provide for combining the partials with any desired intensity, thereby enabling the instrument to produce musical notes having the same timbre or quality of notes sounded on different musical instruments. By way of example I have illuustrated one of the circuit wires in Figure 9 as provided with means for controlling the intensity of one of the partials, namely, the partial corresponding to the tuning fork 133:1. In order to accomplish this I provide the regenerating circuit wire 211 corresponding to this partial with a plurality of resistances 212 of different values, each resistance having a corresponding electrical switch 213.

These electrical switches are controlled at will through other switches, such as the switch 214.

By closing any desired electric switch, the circuit from the wire 211 can be made to pass through any one of the different resistances 212, thereby controlling the volume of sound produced by this vibrator or tuning fork 133d. In practice, if desired, the corresponding regenerating circuit for every partial fork would have a corresponding selective resistance. In this Way I can not only play any desired partial or combination of partials, but can, at will, give the partials therelative intensity necessary to give the diierent quality of tones corresponding to different orchestral instruments.

In addition to this, if desired, the intensity of the partials may be controlled by regulating the force of the blow delivered by electric hammers, such as the hammer 136. This may be accomplshed in a manner similar to that just described by providing a plurality of resistances 215 of different value connected into one of the circuit wires, such as the circuit wire 148. Between the corresponding switch 154 and the electrical hammer corresponding to this wire I provide three electric switches 216 corresponding to the different resistances 215. Each electric switch is controlled by a corresponding circuit 217 having its corresponding switch. Evidently, by closing the proper switch any one of the resistances 215 can be drawn into the circuit. In practice all of the Wires 148 would be provided with such relative resistances. l

It is understood that the embodiment of the invention described herein is only one of the many embodiments this invention may take, and I do not Wish to be limited in the practice of the invention, nor in the claims, to the particular embodiment set forth.

I claim:

1. In a musical instrument, the combination of a plurality of resilient vibrators capable of vibrating at different periods, electro-mechanical means including a moving part connected to the vibrator for mechanical movement thereby, so that the movement of said part causes impulses in the electro-mechanical means, an electric circuit including the electro-mechanical means, means for amplifying the impulses developed in the circuit by the vibrators, sound translating means for translating the impulses into sounds corresponding thereto, and electro-mechanical means for giving a single impulse to each vibrator.

5 2. In a musical instrument, the combination of a plurality of vibrators capable of vibrating at different periods respectively, corresponding to the notes of a musical scale, means including an electro-magnet adjacent each vibrator, a part mechanically actuated by the vibrator so that the vibration of said part develops impulses in the n electro-magnet, an electric circuit connected with the electro-magnet, means for amplifying the impulses developed in the circuit by the vibrators, sound translating means for translating the impulses into sounds corresponding thereto,

a key corresponding to each vibrator, and an electro-magnet adjacent each vibrator controlled by its corresponding key and operating to give the vibrator a single impulse when the key is depressed.

3. In a musical instrument, the combination of a plurality of vibrators constructed to vibrate at different periods respectively, corresponding to the notes of a musical scale, an electro-magnet having a coil adjacent each vibrator and having an armature mechanically connected with the vibrator so as to be vibrated thereby, an electric circuit connected with the said coil, means for amplifying impulses developed in the circuit by the vibrators, sound translating means for translating the impulses into sounds corresponding thereto, a key corresponding to each vibrator, and

an electro-magnet adjacent each vibrator con-