US2568862A

US2568862A - Electrical musical instrument with vibratory strings

Info

Publication number: US2568862A
Application number: US768403A
Authority: US
Inventors: Martin Constant
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-08-14
Filing date: 1947-08-13
Publication date: 1951-09-25
Anticipated expiration: 1968-09-25

Description

Sept. 25, 1951 c, MARTIN ELECTRICAL MUSICAL. INSTRUMENT WITH Filed Aug. 13, 1947 VIBRATORY STRINGS 5 Sheets-Sheet l N m LL] E a m E 5 R E 5 0 E as 1 m EE R? m {5 m is :2 N if: o=

I J W INVENTOR:

- CONSTANT MARTIN.

ATTORNEY.

P 25, 1951 c. MARTIN 2,568,862

ELECTRICAL MUSICAL INSTRUMENT WITH VIBRATORYI STRINGS Filed Aug. 13, 1947 5 Sheets-Sheet 2 Fig. 2

VARIABLE. RESISTANCE [AMPLIFIER I AMPLIFIER Fig.3

VARIABLE RES! STAN CE. AMPLIFIE INVENTOR:

dons-mm mun-m.

ATTORNEY Sept. 25, 1951 Q MARTIN 2,568,862

ELECTRICAL MUSICAL INSTRUMENT WITH VIBRATORY STRINGS Patented Sept. 25, 1951 ELECTRICAL MUSICAL INSTRUMENT WITH VIBRATORY STRINGS Constant Martin, Versailles, France Application August 13, 1947, Serial No. 768,403 In France August 14, 1946 8 Claims. 1

It is well known that, in a string stretched between two fixed points, if an intermediate point of said string is struck with a movable nut or hammer which remains applied against the string, both portions of the latter as determined by the nut or hammer start vibrating separately. Such vibrations become gradually damped and the time required for such damping depends on the nature of the hammer, on its mass and on the inertia of any parts rigid with said hammer. When the hammer leaves the string and there is no damper provided, the string continues to vibrate throughout its entir length until completely damped out.

The present invention has for its object to provide a musical instrument with vibratory strings which initially utilises the above described phenomenon associated with one or more other phenomena. of electrical or acoustical nature.

It consists of using a. vibrator string made of an electrically conductive material, stretched be tween two points and which is struck at an intermediate point thereof with a movable nut or a hammer of suitably predetermined mass and character, wherein said hammer may be operated either directly or indirectly through any suitable device such as a key of a key-board or the like, and wherein said hammer may, through any appropriate mechanism be caused when desired by the performer, to remain applied against the string as the performer releases the device, key or the like, controlling the operation of the movable nut.

The invention also includes the damping or throttling by means of a suitable damping sys- I tem, the vibrations of one portion of the string so as to use only the vibrations of the other portion. Such acoustic vibrations of the second portion of the string are converted into electric vibrations which are then amplified in an amplifier and reconverted into sound vibrations by means of a loud speaker or any other appropriate means.

In order to prolong the vibrations of that portion of the string which is used, a second movable nut or hammer, operated by any suitable controlmember, is adapted to be applied against the string at the same point as the first hammer or nut, and remains applied thereagainst as the first nut leaves the string and returns to its rest position. Also with the purpose of prolonging the vibrations of the string, another string stretched between two fixed points and tuned. to the same frequency as the main string is caused to vibrate by resonance as said first string vibrates. The vibrations of the second string may also be converted into electric vibrations and amplified and transmitted to a loud-speaker.

The instrument forming the subject matter of this patent application comprises as many elementary devices of the above defined type as may be desired, tuned to the frequencies of one or more octaves of the musical scale, and thus makes it possible to play any desired piece of musical literature.

An embodiment of one of the elements comprising the instrument will now be described by way of illustration and not of limitation:

Fig. 1 diagrammatically illustrates such an elementary device;

Fig. 2 diagrammatically illustrates a modification of the device shown in Fig. l.

Fig. 3 diagrammatically illustrates a second embodiment of the device shown in Fig. 1.

Fig. 4 illustrates diagrammatically a device similar to that shown in Fig. 1 provided with a plurality of elements enabling a vibratory string to be struck at dillerent points so as to secure several musical notes with a single string.

The above figures are given merely by way of example and the devices shown therein are not to be construed as limiting the invention, which may further comprise any variations and modifications in accordance with the spirit thereof.

As may be seen in Fig. 1, the initial vibratory strin is stretched between two points A and B. The hammer or movable nut I is selected with a suitable mass so that the vibrations of the portion CB of the vibratory string will be damped after a sufiiciently long time, when said hammer or nut is maintained applied against the string at a point C.

A lever 2 movable around a pivot 3 carries the hammer or nut I. The end I of the lever 2 is bevelled. A blocking device is provided to block the nut I in the position wherein it is in contact with the vibratory string. Said blocking device comprises a part 9 movable about the pivot I0 and one end I I of which carries a bent plate 8 adapted to latch the lever 2, thereby holding the nut I in contact with the vibrator string.

A secondary hammer or movable nut l4 the end I5 of which is provided with a vibrationdamping material is secured to a lever I2 movable about the pivot I3. Said secondary nut may be held in or out of contact engagement with the string at the point C opposite to the main or primary nut I.

The damper 6 may be made of felt, cloth, sponge rubber or any other suitable material and O is in permanent contact engagement with the string portion AC.

The electric portion of the elementary device comprises a coil 4 surrounding a magnet core 5 spaced a short distance away from the spring portion CD and in such a way that the vibrations of the latter are effective to modify the reluctance of the magnetic circuit of the magnet 5.

The electric circuit for the induction coil '4 is closed through a potentiometer or a variable resistance l5 through the medium ofthe portion CD of the vibratory string and the switchmeans formed by the nut I in contact with the string AB at the point C.

A shunt switch I makes it possible tocause.

the last mentioned switch means to b ineffece tive.

The electric vibrations induced through the coil 4 and the power of which is adjustable by the potentiometer orvariable resistor l6 are fed through an amplifier I? and are then converted into sound vibrations in the loud-speaker I8.

Finally, a string DE stretched a short distance away'from AB and tuned to the same frequency asthe active portion GB of: the string, AB

may be caused to resonate with CB when a damper I9 carried by a lever ZSJmoVable about its pivot 2| is out of contact with the string. A magnetic core 26 surroundedby a coil 23 is spaced ashort distance from the string DE and the output of thecoil 23 is connected through themedium of a variable resistance 25 to the input of the amplifier 26 followed by a loud speaker 27.

The elementary device described above operates as follows:

The player presses on the end of the lever 2 opposite to the nut. Under the impact of the nut, the portion GB of the stringstarts vibrating. The coil 4 then becomes the seat of induced'currents therethrough which afteramplification in the amplifier 1'. actuate the loud speaker I8.. The sound is prolonged until complete damping of the vibrations in the string portion CB, if the nut is held in contact with the string. Th volume of the sound is the greater as the impact of the nut against the String has been stronger and is therefore variable according to the players desire. The sound is brief if the performerallows the nut to drop back immediately after having struck the string, the vibrations in the latter then being stopped immediately.

In the event where thesound is to be prolonged and in order to free the players finger, the device comprising the parts 8, 9, l0, blocks the lever 2 in its lowermost position and consequently blocks the nut l The operation of the latching device may be controlled through a pedal or any other suitable,

means, andin the latched position thus obtained it is possible, lay-once more striking the lever 2, to cause a further extension in the duration of the sound, and the production of particular musical effects.

The performer may also extend the duration of the sound by means of the secondary nut [5. That is, by closing the switch I and bringing the secondary nut 15 into contact with the string, any impact however brief, of the main nut 1 causes vibration. of spring portion CB, the damping time of which depends on the character of the secondary nut E4 and of its support as well as on the. pressure exerted thereby against the string, if'its end I5 is provided with aresilient material. Like the device described in the foreagainst the vibratory string.

going paragraph, this device may also be operated by means of levers or any other appropriate means.

Finally, a resonant system may also be caused to extend the vibrations of the string portion CB and the resonance of the secondary string DE is allowed to be effective by retracting, as desired by the performer, the damper l9. An electric ystem similar to that provided for the main string AB picks up and amplifies the vibrations of the secondary string.

In the modification of Fig. 2 the resonant string DE is electrically controlled through the amplifier H of Fig. 1.

Part of the available energy at the output of theamplifier l! is applied to the string DE, arranged between the arms NS of a magnet. The string DE is therefore energized each time the portion CB of the string of Fig. 1 is caused to vibrate. A pick-up-amplifier-control and loud speaker-rassembly 29.303l--32 identical with the assembly 23-252 3 21 of Fig. 1 converts asbefore the-vibrations of the string.

In the modification shown in Fig. 3 asimilar' result is obtained by reinforcing the-resonance energization of the strings such as DE with one or more loud speakers33 which receive a fraction ofthe. available-energy fromgthe output of the,

amplifier I! of Fig. 1.1 The vibrations of the strings such as DE are converted as before in an assembly 35353T-38.

Anarrangementadapted to provide for the se-v curing of several notes with a single string, is i1- lustrated in Fig. 4. In this arrangement, which is 'in'principle similar to that illustrated and described, with reference to Fig. 1, a plurality; of hammers or nuts areprovided at spaced points along the vibratory string AmBm.- In Fig. 4,

three hammers or'nuts la,- lb, and I0, are showm eachiactuated bylevers 2a, 2b, and 2c, respectively;which levers are pivoted as at 3a, 3b,. and 3c; blocking -devices9a, 9b, and 9c, are pivoted at lila, lob, and IUc, and carrying; at ends Ha, I lb; andjl lc, respectively, the bent plates 8a, 8b, andBc; respectively. In general, therefore, the construction of ithe arrangement illustrated in Fig.,4-is identical with that illustrated and described with reference to Fig. l, with the difference that-instead of a single hammer I being provided with accompanying attachments, three hammers, la, I b, and 10 are provided. The electrical circuit provided is similar to that illustrated with respect to Fig. l, the principal parts'carrying the same reference numbers followed by the letter m.. It will be appreciated that the number of hammers or nuts is not limited to three.

Numerous modifications other than those described herein may readily be devised; Such modifications all derive from the foregoing example. Thus it is possible to make use not only of electro-magnetic systems but also electro-static, electro-dynamic, photo-electric, piezo-electric and other means.

It is also possible for greater simplicity and in thecase of Figs. 2 and 3 to use a single magnetic core such as 29 or 35 for a plurality of strings- Such a core will then be appropriately adapted.

Similarly the feature of disposing the nuts in different ways with respect to the vibratory string is to be considered as implying modification of the present invention, and also the number of said nuts is of no consequence to th present invention.

Furthermore, the position of the nut l in Fig. 1 may be varied and the movable nut or nuts may have any type of motion imparted thereto along the string without such a procedure exceeding the scope of the present invention. In'thiS way special sound effects may be obtained.

According to the invention, smooth strings and extruded or ribbed strings maybe used and in the. latter case a, simple displacement of the nut along the string will sustain the vibrations thereof.

The nuts described in the foregoing disclosure may be simply constituted by the fingers of the performer, without exceeding the scope of the present invention.

It is also possible to embody an instrument in accordance with the present invention which also comprises a small number of strings, the various notes in the scale being obtained by the use of a plurality of nuts arranged at various points along a. common string.

In as much as a number of modifications may g be made in the foregoing construction and the invention is capable of being embodied in a great number of apparently widely diiferent forms without exceeding the scope of this invention as defined in the appended claims, all details mentioned in the foregoing disclosure or shown in the accompanying drawings should be regarded as exemplifying and not as limiting the scope of the present invention.

What I claim is:

1. In an electric musical instrument a sound unit comprising in combination a vibratory string, a hammer for striking said string at an intermediate point thereof, hand-controlled actuating means for said hammer, means for selectively causing said hammer to disengage said string immediately after having struck the same and for causing said hammer to remain in engagement with said string, means for damping the sound vibrations set up in one side of said string, and means for electrically picking up, amplifying and reconverting into sound the sound vibrations set up in the other side of said string.

2. In an electric musical instrument a sound unit comprising in combination a vibrator string V adapted to vibrate at a desired audible frequency, a hammer for striking said string at an intermediate point thereof, hand-controlled actuating means for said hammer, latching means operable for latching said hammer in contact engagement with said string, means for damping the sound vibrations set up in one side of said string, and electric means for picking up, amplifying and reconverting into sound waves the vibrations set up in the other side of said string.

3. In an electric musical instrument a sound unit comprising in combination a vibratory string made of an electrically conductive material, a hammer of electrically conductive material and actuating means to cause said hammer to strike said string at an intermediate point of the length thereof, means for damping the sound vibrations set up in one side of said string, a magnetic core in reluctance-responsive relation with said string at the other side thereof with reference to said intermediate point thereon, an induction coil surrounding said core, induction circuit connections for said coil extending through said string and said hammer so as to make said circuit as said hammer is in contact engagement with said string, volume-control adjustable resistance means in said circuit, an amplifier input in said circuit and a loud-speaker across the output of said amplifier.

4. In an electric musical instrument a sound unit comprising in combination a vibratory string, a hammer for striking said string at an intermediate point thereof, both said string and said hammer consisting of electrically conductive material, hand-controlled actuating means for said hammer and means for blockingsaid hammer in actuated position, means for damping the sound vibrations in one side of said string, a mag netic core in reluctance-responsive relation with said string on the other side of said intermediate point thereof, an induction coil surrounding said core, circuit connections for said coil extending through said string and said hammer so as to be operative when said hammer is in said actuated string-engaging position, sound-volume control adjustable resistance means in said circuit, an amplifier input in said circuit and a loud-speaker across the output of said amplifier.

5. In an electric musical instrument a sound unit comprising in combination a vibratory string of conductive material, a hammer of conductive material adapted to strike said string at an intermediate point thereof, a second hammer actuatable to strike said string substantially at the same point thereof, means for damping the sound vibrations in one side of said string, a magnetic core in closely spaced relation with a point of said string on the other side of said intermediate point, an induction coil surroundin said core, circuit connections for said coil extending through said string and said hammer so as to be closed when said first hammer is in string-engaging position, a manually operable shorting switch in shunt across said first hammer and said string to allow said circuit to be closed when said first hammer is out of contact while said second hammer is in contact with said string, sound-volume potentiometer control means in said circuit, an amplifier the input to which is in said circuit and a loud-speaker across the output of said amplifier.

6. In an electric musical instrument a sound unit comprising in combination a first vibratory string, means for striking said string at an intermediate point thereof, means for damping the vibrations in one side of said string, pick-up means for converting the vibrations in the other side of said string into corresponding electric oscillations, means for amplifying said oscillations and means for reconverting said amplified oscillations into sound, a second string resonant with said first string, means for directing a part of said amplified and reconverted sound energy as derived from said first string to said second string, means for picking up, amplifying and reconverting into sound the resonant vibrations of said second string, and means for damping the vibrations of said second string.

7. In an electric musical instrument a sound unit comprising in combination a, first vibratory string, means for striking said String at an intermediate point thereof, means for damping the vibrations in one side of said string, pick-up means for converting the vibrations in the other side of said string into electric oscillations means for amplifying said oscillations, means for reconverting said oscillations into sound, a second vibratory string of electrically conductive material resonant with said first string, means for supplying a part of said amplified electrical oscillations derived from said first string across said second string, pick-up means for converting the vibrations in said second string into electric oscillations means for amplifying said oscillations and means for reconverting them into sound.

8. An electric musical device comprising a 7 8 string, 'a. plurality of means for striking said REFERENCES CITED string at Spaced pomts thereamng means for The following references are of record in the damping the vibrations in one portion of said fil f this patent; string on one side of each of said points, means for picking up, converting into lectric oscilla- 5 UNITED STATES PATENTS tions, amplifying and reconverting into sound Number Name Date the vibrations in the other side of said string with 472,019 Ohms-rt Mar. 29, 1892 reference to each of said points, said points be- 716,034 Harriss et a1. Dec. 16, 1902 mg so interrelated along said string as to pro- ,988,564 Nernst Jan. 1 5 vide a desired scale or notes. 10 2,001,7 3 Hamm nd M y 2 1 2,185,734 Loar Jan. 2, 1940 CONSTANT MARTIN.