US 3696700 A
A stringed musical instrument having a hollow body and a solid finger board, the body having a channel with which the finger board cooperates and fills the channel, the spacing of the sides of the finger board and that of the body being reduced intermediate the top and bottom of the finger board and body, and insulating material interposed between the sides.
Description (OCR text may contain errors)
United States Patent 1 ,6 6,700
Berardi [451 Oct. 10, 197 2 ELECTRICAL MUSICAL STRINGED 3,439,570 4/1969 Lee ..84/293 INSTRUMENTS 3,443,018 5/1969 Krebs ..84/ l .16 Inventor: Michael P. a di P.0- ox Tcndl'eau et a1. ..84/l-16 5mm, Mlaml FOREIGN PATENTS OR APPLICATIONS  Filed: g 1971 2,001,193 9/1969 France ..84/l.16
 Appl. No.: 168,545 Primary Examiner-Richard B. Wilkinson Assistant Examiner-Lawrence R. Franklin Related US. Application Data Attorney-George A. Degnan  Continuation-impart of Ser. No. 63,849, Aug.
14, 1970, abandoned. ABSTRACT A stringed musical instrument having a hollow body ..84/29l, 84/l.:;61,08;1/32/(9)3 and a solid finger board the body having a channel with which the finger board cooperates and fills the  Field of Search ..84/1.l6, 267, 290, 291, 293 channel the spacing of the sides of the finger board and that of the body being reduced intermediate the  References cued top and bottom of the finger board and body, and in- U I STATES PATENTS sulating material interposed between the sides. 3,396,621 8/1968 Dycus ..84/293 4 Claims, 3 Drawing Figures Iii PATENTEDflcr 10 1972 FIG. 3
' INVENTOR MICHAEL P. BERARDI ATTORNEY ELECTRICAL MUSICAL STRINGED INSTRUMENTS This application is a continuation-in-part of the application of Michael P. Berardi, Ser. No. 63,849, filed Aug. 14, 1970 for Electrical Stringed Instrument now abandoned.
The present invention relates to electrical stringed musical instruments, particularly guitars in which sound amplification means and the source of electrical power are contained in the body of the instrument. More particularly, the invention pertains to a novel form of finger board and parts of the body with which the finger board cooperates together with means interposed between the finger board and body providing sound insulation so that feed back to the conventional electro-magnetic pick-up is minimized if not entirely eliminated.
It is an object of the invention so to construct the instrument that feed back is reduced to such a degree that the magnitude of electric power can be substantially increased with an accompanying increase in sound volume.
It is a further object of the invention to assemble the finger board and body by means other than metallic fasteners thereby to reduce feed back.
Other objects will be apparent from the following description of the invention, reference being had to the accompanying drawings, in which:
FIG. 1 is a top plan view of a preferred form of the invention,
FIG. 2 is a sectional view taken on line 2-2 of FIG. 1, and
FIG. 3 is a diagram of a conventional wiring connecting the sound amplification means of the instrument. 5
Referring to the drawings, the body of the instrument comprises a top 11, a bottom 12, side members 13 and centrally located curved portions 14 forming a channel 15, the depth of which is the same as the height of the sides 13. The channel is open at its forward end 16 and closed at its rear end 17, the latter end terminating forwardly of and being spaced from the rear end 18 of the instrument. Disposed within channel is the enlarged rear portion 21 of a finger board 19 having thereon a bridge 20 over which one end of strings 22 is supported and secured beneath base 29. The other ends of the strings are attached to the customary tuning keys 23. An electro-magnetic pick-up 30 disposed in proximity to the strings 22 is connected by conventional wiring to an amplifier 24, batteries and speakers 26, as shown in FIG. 3 in which string vibrations are transmitted through pick-up to the amplifier 24 when the latter is activated by the closing of switch 34 to complete the circuit from batteries 25 to the grounded amplifier. Loud speaker 26 produces the amplified sound. Decorative plates 32, 33 provide covering for insulation shown at 31.
As shown in FIG. 2, the cross-sectional shape of that portion 21 of finger board 19 disposed in channel 15 is such that the vertical sides 28 are preferably concavely curved and the sides 14 of the channel are complementary thereto. The portion 21 is coextensive in length and depth with that of channel 15 but its vertical sides are spaced from the sides of the channel. Thus the space between the sides of the finger board intermediate the top and bottom thereof isreduced. The spacing between the sides of the channel is similarly reduced. interposed in the spaces between these sides are two relatively thick layers of sound insulating material identified by the reference characters 31a, 31b, 31c and 31d. The layers 31a and 31b are adhesively attached to the finger board, the layers 31c and 31d being adhesively attached to. body in channel 15. The unattached abutting faces of the layers are relatively smooth, permitting the finger board and its attached sound insulating layer to be inserted lengthwise into the channel. The combined thickness of the layers of insulation on each side of the finger board is slightly greater than the spacing between the finger board and the body so that the insulation is compressed sufficiently to provide a firm tight fit but will not prevent disassembly when necessary. With this type of construction it will be apparent that sounds emanating from within the hollow body of the instrument will be prevented from being transmitted to the finger board by the interposition of the sound insulating material.
The material from which the body and finger board are produced is preferably wood but the material of the finger board may be any of several types of moldable plastics, light weight metal or other suitable materials since it does not reflect sound. The placement of the amplifying elements and the speakers is discretionary with the assembler so long as distribution of the weight of these is suitably balanced.
It is to be noted and emphasized that there is no metallic means attaching the finger board to the body other than two small wires extending from the pick up to the amplifier. The parts of the body and the amplifying components may be assembled with adhesive bonding means or a minimum of metallic fastening means which, however, do not conduct sound to the insulated finger board or transmit feed back to the pick up. It is also to be noted that the particular shape of the sides of the finger board and the complementary sides of the channel prevent displacement of the finger board in a direction normal to the top and bottom of the instrument or by rotation of the finger board, movement thereof being confined to a longitudinal or axial direction.
A preferred form of the invention has been illustrated and described but such modifications as fall within the terms of the appended claims are contemplated.
What is claimed is:
I. An electrical stringed musical instrument comprising a body having top and bottom portions, side portions connecting said top and bottom portions, a channel formed by spaced members extending between and connected to said top and bottom portions, said channel extending rearwardly from the front end of said instrument, said channel being open at its forward end and closed at its rear end, a finger board coextensive with the length and depth of said channel, the spacing between the sides of the finger board being reduced intermediate the top and bottom thereof, the sides of the channel being complementary to the sides of the finger board and being spaced laterally from the sides of said finger board, sound insulating material interposed between the sides of said finger board and said channel, the thickness of said insulating material being slightly greater than the spacing between the sides of the channel and the sides of said finger board whereby said and a layer of material secured to each side of said m channel.
3. A musical instrument as defined in claim 2, in which the sides of the channel are convex and the sides of the finger board areconcave with respect to the longitudinal axis of the finger board.
4. A musical instrument as defined in claim 2, in which the finger board is longitudinally slidable within said channel.