Title:
ELECTRONIC STRINGED MUSICAL INSTRUMENT WITH PLURAL RESONATORS AND PICKUP
United States Patent 3595981


Abstract:
An electronic stringed musical instrument in which the vibrations of the strings are transmitted to resonant beams, the vibrations in said beams are transmitted to a common electromechanical transducer, and the electricaL signal thus generated is amplified and converted into sound.



Inventors:
HOPPING ALVIN S
Application Number:
04/846473
Publication Date:
07/27/1971
Filing Date:
07/31/1969
Assignee:
ALVIN S. HOPPING
Primary Class:
Other Classes:
84/731, 984/371
International Classes:
G10H3/18; (IPC1-7): G10F1/02
Field of Search:
84/1
View Patent Images:
US Patent References:
3325580Musical instrument utilizing piezoelectric transducerJune 1967Barcus et al.
3003382Electric violin, and electromagnetic pickup thereforOctober 1961Fender
2539297Electric musical instrumentJanuary 1951De Lazaro
2020557Stringed musical instrumentNovember 1935Loar



Primary Examiner:
Hirshfield, Milton O.
Assistant Examiner:
Weldon, Ulysses
Claims:
What I claim is

1. An electronic stringed musical instrument comprising a bridge, a plurality of vibratory musical strings tensioned against said bridge, a plurality of resonant beams to which vibrations of said strings are transmitted through said bridge, a pickup spanner mounted transversely across said resonant beams and into which the vibrations of said beams are coupled therefrom, and an electromechanical transducer for converting the vibrations coupled into said spanner into electrical signals.

2. An electronic stringed musical instrument as set forth in claim 1 in which said resonant beams are wooden beams which are pretuned to resonate at semitones of the musical scale.

3. An electronic stringed musical instrument as set forth in claim 1 in which said transducer is resiliently mounted on and entirely supported by said pickup spanner, thereby being acoustically insulated from all other members of said musical instrument.

4. An electronic stringed musical instrument as set forth in claim 1 having a wooden spanner bar which is transversely mounted across said resonant beams and on which said bridge is mounted.

5. An electronic stringed musical instrument as set forth in claim 1 in which said pickup spanner is ferromagnetic and in which said transducer includes a pickup coil and a permanent magnet magnetically coupled to said coil to form a magnetic circuit in which vibrations coupled to said pickup spanner from said beams generate electric signals.

6. An electronic stringed musical instrument as set forth in claim 1 in which a resilient coupling member is mounted on said pickup spanner, and said transducer includes a piezoelectric cartridge supported on said resilient coupling member, vibrations in said spanner being transmitted to the sensing element of said cartridge from said pickup spanner through said resilient coupling member.

7. A bowed electronic stringed musical instrument comprising a plurality of strings adapted to be bowed; a two-legged bridge against which said plurality of strings bear; a plurality of pretuned resonant wooden beams and a wooden spanner bar transversely mounted along the central longitudinal portion thereof and carrying said bridge, from which bridge vibrations of said strings are transmitted to said resonant wooden beams, said beams being disposed in a substantially parallel manner in a common plane and extending from a common line of origin; a pickup spanner mounted transversely across all of said pretuned beams near the common line of origin thereof and into which the vibrations of said beams are coupled; a resilient coupling member mounted on said pickup spanner; an electromechanical transducer having a sensing element which is coupled to said pickup spanner through said resilient coupling; an amplifier for accepting the electrical output of said transducer and amplifying it; and means for converting said amplified signal into sound.

Description:
This invention relates to electronic stringed musical instruments. More particularly, it relates to electronic stringed musical instruments which are bowed, i.e. of the type of violins, violas, and cellos, and which may use conventional strings, fingerboard and bow.

Only a few of the most expensive conventional violins have a uniform volume output, note to note, and the reputation of the famous old instrument makers is largely based on such uniformity of output. Using conventional violin strings, fingerboard and bow, this problem has now been overcome by means of the instant invention in which a beam resonator, preferably a broadly tuned wooden beam, is supplied for each semitone of the musical scale and reinforces these notes when played. Inasmuch as audible output is provided by electronic amplification and a loudspeaker system, each of these tuned wooden strips can be small and all can be placed in a somewhat smaller area than that of a violin top.

The instant device also offers the advantage that in manufacture, an output or resonance curve can be taken from a prototype instrument and any needed change narrowed down to the specific beam involved and slight alterations made in it. Thus, an instrument can be produced which is much more uniform in output than the conventional violin. Since there are not curved surfaces, all parts can be accurately measured after the prototype instrument is finally completed and the prototype can be duplicated without difficulty.

Previous attempts at electronic amplification of string tones has resulted in unwanted amplification of sounds from handling of the instrument, increase in bow scrape, objectionable thump from finger placement in selecting the notes, and feedback howl. In the musical instrument of the present invention these undesirable conditions have been avoided by use of resilient mountings and spanner averagers at appropriate locations. A preferred magnetic pickup is employed which is characterized by high amplification and low microphonics due to its closed magnetic circuit and substantially constant spacing between its fixed permanent magnets and its movable armature element, which in this instance suitably is a spanner element.

Although the present instrument produces a characteristic violin sound of eminent quality, its voice quality can be changed by available electronic techniques so the instrument can have string tone, brass horn tone, or sax voice. The range of the instrument can be extended from violin to cello by lowering its pitch one octave by means of electronic frequency division. Voicing not available on the conventional violin may be obtained with volume sufficient to satisfy any musician. The instrument is also characterized by prompt response to the demands of musicians with respect to fast attack and fast decay.

Various other features and advantages of the musical instrument of the present invention will become apparent on consideration of the following embodiment as more completely illustrated in connection with the accompanying drawings.

In the drawings:

FIG. 1 is a view in section of an electronic violin in accordance with the present invention;

FIG. 2 is a plan view along the line 2-2 of FIG. 1 taken in the direction shown;

FIG. 3 is a view on an enlarged scale of a conventional bridge as used in the instant instrument;

FIG. 4 is an end view, on an enlarged scale, of a crystal pickup structure which may be used in the device of FIG. 1 in lieu of the electromagnetic pickup employed therein; and

FIG. 5 is a side view of the pickup of FIG. 4 taken along the line 5-5 thereof in the direction shown.

In the figures, a conventional bow (not shown) is used with a fingerboard 10 which is mounted on a neck 12 having a peg box 14 and scroll 20. The neck 12 supports four violin strings 22 in the usual manner. The strings 22 are supported at the outer end of the fingerboard 10 by a nut 26, and pass over a conventional two-legged bridge 30 (best illustrated in FIG. 3). Tension is maintained on the strings by a tailpiece 32, which is affixed to an end pin 36.

The end pin 36 is carried by a block 38, and both the block and the neck 12 are affixed to a rigid, substantially nonresonant back 40. The bridge 30 is cemented by its two feet 44 and 46 (best seen in FIG. 3) to a wooden spanner bar 50, which in turn is cemented across four pretuned resonant beams 52, 54, 56, and 58, each pretuned to resonate at a different semitone of the musical scale. These wooden beams are made of redwood and are dimensioned to resonate broadly at appropriate frequencies before installation. The wooden beams are characterized, of course, by a relatively high flexibility, being characterized by a young's modules of elasticity of less than 2×106, i.e., 1.5×106. Thus, the beams exhibit substantial displacement when stressed, which in turn generates a high-level output in the transducer associated therewith. The wooden spanner bar 50 is also made of redwood.

The resonant beams 52, 54, 56 and 58 are, in turn cemented to resilient rubber mounting pads. One pad 60 is cemented to the nodal point of each resonant beam, and a second pad 64 is cemented to the resonant strips in the proximity of the wooden spanner bar 50. The preferred position is, as shown in FIG. 2, slightly toward the aligned ends of the resonant beams 52, 54, 56 and 58, and the cement employed in the instant device is of the nonrigid type so that a flexible, resilient, pliant elastic condition is maintained.

The resonant beams are disposed in a common horizontal plane in a generally parallel fashion with one end of each beam being disposed along a common line. The resilient pads 60 and 64, which are cemented on their upper surface to the beams 52, 54, 56 and 58, are also cemented on their lower surfaces to the back 40.

A steel pickup spanner 70 is cemented transversely across the top faces of the beams 52, 54, 56 and 58 at their aligned ends. A resilient rubber spacer 72 is, in turn, cemented to the steel pickup spanner 70. A air of coils 76 are mounted side by side along the length of the resilient spacer 72, and each coil 76 has an iron core 79 which is cemented at one end to the upper surface of the resilient spacer 72. Each core 79 extends upwardly through a coil 76 to one of two permanent magnets 80. A steel strip 84 bridges the two magnets 80, to act as a pole-closing member.

The permanent magnets 80 create a magnetic circuit in which the magnetic flux passes from one magnet through the core 79 of the associated pickup coil 76, thence across the gap provided by the resilient spacer 72 to the steel pickup spanner 70. The magnetic flux continues through the steel pickup spanner 70, recrosses the resilient spacer 72 to enter the other pickup coil 76 and core 79, passes through the other permanent magnet 80, and then crosses the pole-closing steel strip 84 to complete the circuit to the original permanent magnet.

In operation, when the strings 22 are played with a bow, the vibrations of these strings are carried by the bridge 30 to the wooden spanner bar 50. Since the resonant beams 52, 54, 56 and 58 are made of wood, they have a fairly low "Q" and are broadly tuned. The vibrations of the resonant beams are transmitted to the steel pickup spanner 70 at the ends of the beams, and the vibrations of the steel pickup spanner 70 to modify the flux gap across the resilient spacer 72 under each core (as in a variable reluctance transducer), thus generating an output signal in the coils 76.

The output signal from the coils 76 is transmitted by wire leads 90 and 92 to an amplifier 94 through optional voicing filters 96 and thence to a loudspeaker 100.

The electromagnetic pickup system illustrated in FIGS. 1--3 may be replaced by a piezoelectric device as illustrated in FIGS. 4 and 5.

In the embodiment of FIGS. 4 and 5, a ceramic phonograph cartridge 106 is fitted with a needle-clamping screw 110. In place of a needle, a wire 112 having a diameter of 0.040 inches is shaped to depend from the cartridge 106 and is then bent laterally to a horizontal position to form an arm which is cemented to a comparatively thin resilient rubber pad 120, which in turn is cemented to the pickup spanner 70. The body of the cartridge 106 is also cemented to an appreciably thicker resilient rubber block 122 which is also cemented to the pickup spanner 70. The cartridge 106, the pickup spanner 70, and the wire 112 interact to pick up vibrations from the beams 52, 54, 56 and 58 and generate therefrom electrical signals in the cartridge which are carried by the leads 90 and 92 to the balance of the instrument as shown in FIGS. 1--3.

The electromechanical transducers of FIGS. 1--3 and the piezoelectric transducer of FIGS. 4--5 are acoustically insulated from the case of the instrument as a whole, being entirely supported on the pickup spanner 70. In addition, the beams 52, 54, 56 and 58 are also resiliently mounted. This is highly advantageous in that the problems of unwanted amplification of sounds generated from handling the instrument, including increased bow scrape and objectionable thump from finger placement in selecting the notes to be played, are eliminated. Other advantages of the instant instrument are that, if desired, the resonant beams 52, 54, 56 and 58 may be fabricated to duplicate the resonant peaks and output qualities of famous old instruments, and that they may also be pretuned to tones below, between, or above the string tones.