US 3826171 A
A classic guitar string made of a synthetic plastic material, such as polyester fibers, with minimum possible stretch so as not to go out of tune, combined with a magnetic material, such as iron oxide, to permit the use of a magnetic pick-up for an amplifier, which picks up the magnetic vibrations only. In one form fine resilient iron wire is wound in close coil around Dacron fibres so that all the tension remains at all times on the fibres of the string and none of the tension on the fibres is taken up by the coil.
Description (OCR text may contain errors)
1111. 9,826,171 1451 July 30,1974
, GUITAR STRING 76 Inventor: James L. Kaar, 519121115 $1., San
Francisco, Calif. 1
221 Filed: Sept. 30, 1971 211 Appl.No.:185,281
Related US. Application Data  Continuation-impart of Ser. No. 29,841, April 20,
lnfeldml 84/297 s 2,762,251 9/1956 3,120,144 2/1964 Bayer 84/297 S X FOREIGN PATENTS OR APPLICATIONS 1,190,769 10/1959 France ..84/297S Primary Examiner-Lawrence R. Franklin Attorney, Agent, or Firm-George B. White  ABSTRACT A classic guitar string made of a synthetic plastic material, such as polyester fibers, with minimum possible stretch so as not to go out of tune, combined with a magnetic material, such as iron oxide, to permit the use of a magnetic pick-up for an amplifier, which picks up the magnetic vibrations only. In one form fine resilient iron wire is wound in close coil around Dacron fibres so that all the tension remains at all times on the fibres of the string and none of the tension on the fibres is taken up by the coil.
2 Claims, 7 Drawing Figures PATENTEDJULEOIQH 3.826.171
sum ear-2 .desirable noises.
ing application Ser. No. "29,841, filed Apr. 20, 1970,
now abandoned. I
BACKGROUND OF THE INVENTION I I In order to amplify the sound of a guitar, classic guitars heretofore worked with sound amplification through a microphone, and electric guitars worked by transmission of the vibration of magnetic metal strings relatively to a magnetic field and amplification of magnetic vibration ultimately converted into sound with less distortion than the classic guitar microphone transmission. I I
In the prior art the classic guitar was strung with copper wire wound around nylon or other strings which had to be partially amplified with an audio microphone which when turned up to the conversational noise level of the room reaches the feedback threshhold and produced a sound similar to howling, whereupon the performer had to stop playing entirely. This previous amplification of classic guitars in noisy public places also reproduced strong noise and other extraneous and un- Attempts were made also to utilize a metal core with an exterior flaky metal coating with a plastic binder on to the metal core, but the same had the disadvantage of sounding differently-than the classic guitar, and re-' sulted in a different touch and feel for the player and in some instances increased the weight of the string and thereby resulted in different type of manipulation and sounding from the usual classic guitar strings.
The primary object of this invention is to combine magnetic metal with a plastic string of the type in which stretch is minimal and which maintains tuning even better than the usual classic strings, and which becomes magnetic so as to permit theuse of the classic guitar with a magnetic pick-up and amplifier system which magnifies only the magnetic vibrations but locks out feedback, strong noise and all other extraneous and undesirable noises, and wherein the magnetic vibrations truly correspond to the vibrations of the plastic string or core, and the natural classic guitar string tension is preserved.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective fragmental view on an enlarged scale of a synthetic plastic solid string with a magnetic coil wound around it.
FIG. 2 is a fragmental side view on an enlarged scale indicating synthetic plastic filaments held together by a magnetic wire tightly wound around a bundle of filaments.
FIG. 3 is a cross-sectional view, the section being taken on lines 3-3 of FIG. 2.
FIG. 4 is a fragmental view on an enlarged scale of a string made of filaments and showing a plastic tape wound outside of the magnetic coil.
FIG. 5 is a cross-sectional view, the section being taken on lines 5-5 of FIG. 4.
FIG. 6 is a fragmental view on an enlarged scale of a magnetic coil imbedded within a synthetic plastic solid string.
FIG. 7 is a fragmental view on an enlarged scale of a plastic string with magnetic particles imbedded therein.
DETAILED DESCRIPTION In the classic guitar the first three strings, namely E #l),B( #2) andG( #3), are usuallymadeofauni' tary nylon string, while the other three strings, namely D 4), A 5) and low F I 6), are usually made of a bundle of nylon filaments previously held together by a copper wire coil.
In playing a guitar, synthetic plastic strings such as Dacron or nylon require less tension than metal strings. In the various embodiments herein, the natural tension of theplastic stringor core is preserved, and magnetic metal is so combined with the plastic string as to be capable of vibration and pitch sympathetic to those of the plastic string, for corresponding vibration of the usual magnetic coil in the magnetic field of the armature of a magnetic pick-up.
In the form shown in FIG. 1 a unitary Dacron string 1 is surrounded by a resiliently yieldable magnetic In the form shown in FIGS. 4 and 5, the bundle of plastic filaments are held together by a resiliently yieldable coil 7 made of magnetic wire, and then covered by thin plastic tape 8 wound around and over the coil 7.
FIG. 6 illustrates the imbedding of a resiliently yieldable spring coil 9 of magnetic material within the body of the solid plastic string 10, said spring coil being fine and of such resiliency as to minimize interference with the natural tensionof the plastic string.
FIG. 7 illustrates iron oxideparticles 11 substantially evenly distributed throughout the body of the solid synthetic plastic string 12..Such particles can be similarly imbedded also in synthetic plastic fibers forming the filaments.
'The synthetic plastic string treated or magnetized, as herein described, substantially preserves its classic guitar tension, and the resiliently yieldable magnetic coils conform to yielding and vibration of the unitary plastic string or the plastic filaments, and act on the field of a magnetic pick-up for high fidelity amplification. When the magnetic particles are imbedded in the plastic string they vibrate with the string and transmit to the magnetic pick-up.
It is preferable to use a synthetic plastic filament of low elasticity, high strength and low stretch so that the string does not go out of tune On account of stretching, and therefore does not require continuous tuning even during playing, yet it should give the flexibility and easy playing action previously enjoyed only by the classic guitarist. I-Ience strings made in accordance with the herein invention would also improve the playing on an electric jazz guitar.
Among the synthetic plastic fibers or filaments, at present, the best with respect to low elasticity, high strength and low stretch, is the filament made of polyester fiber, made from ethylene glycol and terephthalic acid, commonly called Dacron.
1. A guitar string comprising, a body of synthetic plastic material, and magnetic metal particles imbedded in said body, said particles being substantially evenly distributed throughout said body.
2. A guitar string as in claim 1 wherein said plastic material is Dacron.
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